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id="menu-item-26571" class="menu-item menu-item-type-custom menu-item-object-custom menu-item-top-level menu-item-top-level-7"><a href="https://www.physicsforums.com/" itemprop="url" tabindex="0"><span class="avia-bullet"></span><span class="avia-menu-text">Forums</span><span class="avia-menu-fx"><span class="avia-arrow-wrap"><span class="avia-arrow"></span></span></span></a></li><li id="menu-item-search" class="noMobile menu-item menu-item-search-dropdown menu-item-avia-special" role="menuitem"><a aria-label="Search" href="?s=" rel="nofollow" data-avia-search-tooltip=" <search> <form role="search" action="https://www.physicsforums.com/insights/" id="searchform" method="get" class=""> <div> <input type="submit" value="" id="searchsubmit" class="button avia-font-entypo-fontello" title="Enter at least 3 characters to show search results in a dropdown or click to route to search result page to show all results" /> <input type="search" id="s" name="s" value="" aria-label='Search' 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class='page-heading-container clearfix'><section class="author-box" itemprop="author" itemscope="itemscope" itemtype="https://schema.org/Person" ><span class='post-author-format-type blog-meta'><span class='rounded-container'></span></span><div class='author_description '><h3 class='author-title '>About <span class='author-box-name' itemprop="author" >Mark Stuckey</span></h3><div class='author_description_text' itemprop="description" ><p>PhD in general relativity (1987), researching foundations of physics since 1994. Coauthor of "<a href="https://books.google.com/books/about/Beyond_the_Dynamical_Universe.html?id=9u9IDwAAQBAJ&printsec=frontcover&source=kp_read_button#v=onepage&q&f=false">Beyond the Dynamical Universe</a>" (Oxford UP, 2018).</p></div><span class="author-extra-border"></span></div></section></div><h4 class='extra-mini-title widgettitle'>Entries by Mark Stuckey</h4><article class="'post-entry post-entry-type-standard post-entry-46583 post-loop-1 post-parity-odd blog-grid with-slider post-46583 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: PBS Video Comment: “What If Physics IS NOT Describing Reality”" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/pbs-video-comment-what-if-physics-is-not-describing-reality/" rel="bookmark" title="Permanent Link: PBS Video Comment: “What If Physics IS NOT Describing Reality”">PBS Video Comment: “What If Physics IS NOT Describing Reality”<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2024-07-22T11:24:16-05:00" >July 22, 2024</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/pbs-video-comment-what-if-physics-is-not-describing-reality/#comments" class="comments-link" >3 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>PBS Space Time produces some very good videos on the foundations of quantum mechanics (QM), so let me comment on their video What If Physics IS NOT Describing Reality to provide (crucial) missing information. This comment pertains only to the first 9 min of the video, i.e., it has nothing to do with “entropic uncertainty,”…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-45596 post-loop-2 post-parity-even blog-grid with-slider post-45596 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Schrödinger’s Cat and the Qbit" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/schrodingers-cat-and-the-qbit/" rel="bookmark" title="Permanent Link: Schrödinger’s Cat and the Qbit">Schrödinger’s Cat and the Qbit<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2024-04-02T08:51:19-05:00" >April 2, 2024</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/schrodingers-cat-and-the-qbit/#comments" class="comments-link" >27 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>The concept of quantum superposition (or superposition for short) is very counterintuitive, as Schr##\ddot{\text{o}}##dinger noted in 1935 writing [1], “One can even set up quite ridiculous cases.” To make his point, he assumed a cat was closed out of sight in a box with a radioactive material that would decay with 50% probability within an…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-43331 post-loop-3 post-parity-odd blog-grid with-slider post-43331 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics tag-quantum-theory"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: How Quantum Information Theory Solves “the only mystery” of Quantum Mechanics" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/how-quantum-information-theory-solves-the-only-mystery-of-quantum-mechanics/" rel="bookmark" title="Permanent Link: How Quantum Information Theory Solves “the only mystery” of Quantum Mechanics">How Quantum Information Theory Solves “the only mystery” of Quantum Mechanics<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2023-06-03T08:49:50-05:00" >June 3, 2023</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/how-quantum-information-theory-solves-the-only-mystery-of-quantum-mechanics/#respond" class="comments-link" >0 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In Chapter 37 of “The Feynman Lectures on Physics Volume 1,” Richard Feynman famously wrote that the mystery of wave-particle duality in the double-slit experiment is: a phenomenon which is impossible, absolutely impossible to explain in any classical way, and which has in it the heart of quantum mechanics. In reality, it contains the only…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-40248 post-loop-4 post-parity-even blog-grid with-slider post-40248 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-entanglement tag-quantum-experiment tag-quantum-physics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Superdeterminism and the Mermin Device" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/superdeterminism-and-the-mermin-device/" rel="bookmark" title="Permanent Link: Superdeterminism and the Mermin Device">Superdeterminism and the Mermin Device<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2022-03-20T08:01:19-05:00" >March 20, 2022</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/superdeterminism-and-the-mermin-device/#comments" class="comments-link" >140 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>Superdeterminism as a way to resolve the mystery of quantum entanglement is generally not taken seriously in the foundations community, as explained in this video by Sabine Hossenfelder (posted in Dec 2021). In her video, she argues that superdeterminism should be taken seriously, indeed it is what quantum mechanics (QM) is screaming for us to…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-39200 post-loop-5 post-parity-odd blog-grid with-slider post-39200 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: How Quantum Information Theorists Revealed the Relativity Principle at the Foundation of Quantum Mechanics" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/how-quantum-information-theorists-revealed-the-relativity-principle-at-the-foundation-of-quantum-mechanics/" rel="bookmark" title="Permanent Link: How Quantum Information Theorists Revealed the Relativity Principle at the Foundation of Quantum Mechanics">How Quantum Information Theorists Revealed the Relativity Principle at the Foundation of Quantum Mechanics<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2021-07-25T07:48:35-05:00" >July 25, 2021</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/how-quantum-information-theorists-revealed-the-relativity-principle-at-the-foundation-of-quantum-mechanics/#comments" class="comments-link" >12 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>This Insight is a condensed version of No Preferred Reference Frame at the Foundation of Quantum Mechanics. Reference numbers here correspond to that paper. This Insight is an expanded version of Quantum information theorists produce new ‘understanding’ of quantum mechanics. Feynman famously said, “I think I can safely say that nobody understands quantum mechanics” [1]. Despite…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-30350 post-loop-6 post-parity-even blog-grid with-slider post-30350 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-spacetime tag-time-dilation"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Does the Block Universe of Physics Mean Time is an Illusion?" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/does-the-block-universe-of-physics-mean-time-is-an-illusion/" rel="bookmark" title="Permanent Link: Does the Block Universe of Physics Mean Time is an Illusion?">Does the Block Universe of Physics Mean Time is an Illusion?<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2020-09-28T07:49:00-05:00" >September 28, 2020</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/does-the-block-universe-of-physics-mean-time-is-an-illusion/#comments" class="comments-link" >29 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>I have written many Insights (and coauthored an entire book) explaining how the puzzles, problems, and paradoxes of modern physics can be attributed to our dynamical bias and resolved by rising to Wilczek’s challenge [1]: A recurring theme in natural philosophy is the tension between the God’s-eye [4D] view of reality comprehended as a whole…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-30637 post-loop-7 post-parity-odd blog-grid with-slider post-30637 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-physics tag-special-relativity"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: A Principle Explanation of the “Mysteries” of Modern Physics" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/a-principle-explanation-of-the-mysteries-of-modern-physics/" rel="bookmark" title="Permanent Link: A Principle Explanation of the “Mysteries” of Modern Physics">A Principle Explanation of the “Mysteries” of Modern Physics<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2020-08-28T08:20:01-05:00" >August 28, 2020</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/a-principle-explanation-of-the-mysteries-of-modern-physics/#comments" class="comments-link" >96 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>All undergraduate physics majors are shown how the counterintuitive aspects (“mysteries”) of time dilation and length contraction in special relativity (SR) follow from the light postulate, i.e., that everyone measures the same value for the speed of light c, regardless of their motion relative to the source (see this Insight, for example). And, we can…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-29426 post-loop-8 post-parity-even blog-grid with-slider post-29426 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-astronomy tag-cosmology tag-dark-matter tag-supernova"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Dark Energy Part 3: Fitting the SCP Union 2.1 Supernova Data" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/dark-energy-part-3-fitting-the-scp-union-2-1-supernova-data/" rel="bookmark" title="Permanent Link: Dark Energy Part 3: Fitting the SCP Union 2.1 Supernova Data">Dark Energy Part 3: Fitting the SCP Union 2.1 Supernova Data<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2020-04-25T04:52:25-05:00" >April 25, 2020</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/dark-energy-part-3-fitting-the-scp-union-2-1-supernova-data/#respond" class="comments-link" >0 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In Part 1 of this 3-part series, I explained kinematics in Einstien-deSitter (EdS) cosmology and in Part 2, I explained kinematics in ##\Lambda##CDM cosmology (essentially EdS plus a cosmological constant ##\Lambda##). Now I will bring those models to bear on the Supernova Cosmology Project (SCP) Union2.1 type Ia supernova data. This will show clearly how…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-29394 post-loop-9 post-parity-odd blog-grid with-slider post-29394 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-cosmology tag-dark-matter"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Dark Energy Part 2: LCDM Cosmology" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/dark-energy-part-2-lcdm-cosmology/" rel="bookmark" title="Permanent Link: Dark Energy Part 2: LCDM Cosmology">Dark Energy Part 2: LCDM Cosmology<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2020-04-21T10:52:15-05:00" >April 21, 2020</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/dark-energy-part-2-lcdm-cosmology/#respond" class="comments-link" >0 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>This is Part 2 of a 3-part series explaining evidence for so-called “dark energy” leading to a current positive cosmological acceleration. The evidence comes from fitting the SCP Union2.1 type Ia supernova data which indicates the existence of a cosmological constant ##\Lambda## (read “Lambda”, thus ##\Lambda##CDM is sometimes written LCDM) in Einstein’s equations (EEs) of…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-29316 post-loop-10 post-parity-even blog-grid with-slider post-29316 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-cosmology tag-supernova"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Dark Energy Part 1: Einstein-deSitter Cosmology" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/dark-energy-part-1-einstein-desitter-cosmology/" rel="bookmark" title="Permanent Link: Dark Energy Part 1: Einstein-deSitter Cosmology">Dark Energy Part 1: Einstein-deSitter Cosmology<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2020-04-07T16:45:06-05:00" >April 7, 2020</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/dark-energy-part-1-einstein-desitter-cosmology/#comments" class="comments-link" >6 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In this 3-part series, I want to motivate the (re)introduction of the cosmological constant ##\Lambda## into Einstein’s equations of general relativity (GR) per the Supernova Cosmology Project (SCP) Union2.1 type Ia supernova data. As you probably know, this discovery won Perlmutter, Schmitt, and Riess the 2011 Nobel Prize in Physics “for the discovery of the accelerating…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-26091 post-loop-11 post-parity-odd blog-grid with-slider post-26091 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-entanglement tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Answering Mermin’s Challenge with the Relativity Principle" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/answering-mermins-challenge-with-wilczeks-challenge/" rel="bookmark" title="Permanent Link: Answering Mermin’s Challenge with the Relativity Principle">Answering Mermin’s Challenge with the Relativity Principle<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2019-10-25T13:57:37-05:00" >October 25, 2019</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/answering-mermins-challenge-with-wilczeks-challenge/#comments" class="comments-link" >89 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>Note: This Insight was previously titled, “Answering Mermin’s Challenge with Wilczek’s Challenge.” While that version of this Insight did not involve any particular interpretation of quantum mechanics, it did involve the block universe interpretation of special relativity. I have updated this Insight to remove the block universe interpretation, so that it now answers Mermin’s challenge…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-25928 post-loop-12 post-parity-even blog-grid with-slider post-25928 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-classical-physics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Exploring Bell States and Conservation of Spin Angular Momentum" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/bell-states-and-conservation-of-spin-angular-momentum/" rel="bookmark" title="Permanent Link: Exploring Bell States and Conservation of Spin Angular Momentum">Exploring Bell States and Conservation of Spin Angular Momentum<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2019-10-16T17:19:38-05:00" >October 16, 2019</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/bell-states-and-conservation-of-spin-angular-momentum/#respond" class="comments-link" >0 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In a recent thread, I outlined how to compute the correlation function for the Bell basis states \begin{equation}\begin{split}|\psi_-\rangle &= \frac{|ud\rangle \,- |du\rangle}{\sqrt{2}}\\ |\psi_+\rangle &= \frac{|ud\rangle + |du\rangle}{\sqrt{2}}\\ |\phi_-\rangle &= \frac{|uu\rangle \,- |dd\rangle}{\sqrt{2}}\\ |\phi_+\rangle &= \frac{|uu\rangle + |dd\rangle}{\sqrt{2}} \end{split}\label{BellStates}\end{equation} when they represent spin states. The first state ##|\psi_-\rangle## is called the “spin singlet state” and it…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-25803 post-loop-13 post-parity-odd blog-grid with-slider post-25803 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-field-theory"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Modern Physics Understood as an Unrecognized Kuhnian Revolution" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/modern-physics-understood-as-an-unrecognized-kuhnian-revolution/" rel="bookmark" title="Permanent Link: Modern Physics Understood as an Unrecognized Kuhnian Revolution">Modern Physics Understood as an Unrecognized Kuhnian Revolution<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2019-10-15T14:55:45-05:00" >October 15, 2019</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/modern-physics-understood-as-an-unrecognized-kuhnian-revolution/#comments" class="comments-link" >16 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>People often claim on Physics Forums and in the foundations community proper that quantum mechanics is “incomplete.” Indeed, Lee Smolin recently wrote [1, p. xvii]: I hope to convince you that the conceptual problems and raging disagreements that have bedeviled quantum mechanics since its inception are unsolved and unsolvable, for the simple reason that the…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-22678 post-loop-14 post-parity-even blog-grid with-slider post-22678 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics tag-quantum-physics tag-quantum-theory"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Quantum Mystery of Wigner’s Friend" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/wigners-friend/" rel="bookmark" title="Permanent Link: The Quantum Mystery of Wigner’s Friend">The Quantum Mystery of Wigner’s Friend<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2018-11-14T12:41:20-06:00" >November 14, 2018</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/wigners-friend/#comments" class="comments-link" >30 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In this Insight I will introduce the quantum mystery called “Wigner’s friend” using Healey’s version [1] of Frauchiger and Renner’s (FR’s) version [2] of Wigner’s version [3]. As with much of physics, the explication becomes more succinct and comprehensible with each successive rendering. I will show how this mystery results from treating classical information (behaving…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-22542 post-loop-15 post-parity-odd blog-grid with-slider post-22542 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics tag-quantum-physics tag-quantum-theory"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Unreasonable Effectiveness of the Popescu-Rohrlich Correlations" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/the-unreasonable-effectiveness-of-the-popescu-rohrlich-correlations/" rel="bookmark" title="Permanent Link: The Unreasonable Effectiveness of the Popescu-Rohrlich Correlations">The Unreasonable Effectiveness of the Popescu-Rohrlich Correlations<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2018-10-23T16:50:39-05:00" >October 23, 2018</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/the-unreasonable-effectiveness-of-the-popescu-rohrlich-correlations/#comments" class="comments-link" >3 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In this Insight, I will show how the Popescu-Rohrlich (superquantum) correlations provide an unreasonable advantage in a particular “quantum guessing game” using a pedagogical counterpart from the book “Totally Random: Why Nobody Understands Quantum Mechanics” by Tanya Bub and Jeffrey Bub (Princeton University Press, 2018). As I showed in my Insight Why the Quantum, the PR correlations violate…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-21261 post-loop-16 post-parity-even blog-grid with-slider post-21261 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Why the Quantum | A Response to Wheeler’s 1986 Paper" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/why-the-quantum-a-response-to-wheelers-1986-paper/" rel="bookmark" title="Permanent Link: Why the Quantum | A Response to Wheeler’s 1986 Paper">Why the Quantum | A Response to Wheeler’s 1986 Paper<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2018-08-04T09:30:06-05:00" >August 4, 2018</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/why-the-quantum-a-response-to-wheelers-1986-paper/#comments" class="comments-link" >397 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>Wheeler’s opening statement in his 1986 paper, “How Come the Quantum?” holds as true today as it did then [1] The necessity of the quantum in the construction of existence: out of what deeper requirement does it arise? Behind it all is surely an idea so simple, so beautiful, so compelling that when — in…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-17078 post-loop-17 post-parity-odd blog-grid with-slider post-17078 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-gps tag-schwarzschild-metric"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Schwarzschild Metric: A Newtonian Comparison" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-3-newtonian-comparison/" rel="bookmark" title="Permanent Link: The Schwarzschild Metric: A Newtonian Comparison">The Schwarzschild Metric: A Newtonian Comparison<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2018-01-01T16:44:08-06:00" >January 1, 2018</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-3-newtonian-comparison/#comments" class="comments-link" >2 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>A Short Proof of Birkoff’s Theorem derived the Schwarzschild metric in units of ##G = c = 1##: \begin{equation} ds^2 = -\left(1 – \frac{2M}{r}\right)dt^2 + \left(1 – \frac{2M}{r}\right)^{-1}dr^2 + r^2d\theta^2 + r^2 \sin^2\theta d\phi^2 \label{metric} \end{equation} and I used that metric in The Schwarzschild Metric: Part 1, GPS Satellites to show that Global Positioning System (GPS) clocks…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-17047 post-loop-18 post-parity-even blog-grid with-slider post-17047 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-gps tag-schwarzschild-metric"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Schwarzschild Metric: The Photon Sphere" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-2-photon-sphere/" rel="bookmark" title="Permanent Link: The Schwarzschild Metric: The Photon Sphere">The Schwarzschild Metric: The Photon Sphere<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2017-12-29T15:59:17-06:00" >December 29, 2017</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-2-photon-sphere/#comments" class="comments-link" >2 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  A Short Proof of Birkoff’s Theorem derived the Schwarzschild metric in units of ##G = c = 1##: \begin{equation} ds^2 = -\left(1 – \frac{2M}{r}\right)dt^2 + \left(1 – \frac{2M}{r}\right)^{-1}dr^2 + r^2d\theta^2 + r^2 \sin^2\theta d\phi^2 \label{metric} \end{equation} and I used that metric in The Schwarzschild Metric: Part 1, GPS Satellites to show that Global Positioning System (GPS)…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-16980 post-loop-19 post-parity-odd blog-grid with-slider post-16980 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-schwarzschild-metric tag-spacetime"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Schwarzschild Metric: GPS Satellites" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-1-gps-satellites/" rel="bookmark" title="Permanent Link: The Schwarzschild Metric: GPS Satellites">The Schwarzschild Metric: GPS Satellites<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2017-12-27T21:16:08-06:00" >December 27, 2017</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/schwarzschild-metric-part-1-gps-satellites/#comments" class="comments-link" >4 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  A Global Positioning System (GPS) device gives your precise location by receiving light pulses from satellites with synchronized clocks then triangulating your location based on that information [1]. Since light travels at 300 million meters per second, your location will be off by about 1 meter if the clock times are off by only…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6442 post-loop-20 post-parity-even blog-grid with-slider post-6442 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-retrocausality"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Understanding Retrocausality and Blockworld" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/retrocausality/" rel="bookmark" title="Permanent Link: Understanding Retrocausality and Blockworld">Understanding Retrocausality and Blockworld<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-11T14:31:17-06:00" >November 11, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In an Insights series “Blockworld and its Foundational Implications,” I quoted Huw Price and Ken Wharton in several places advocating a blockworld approach to physics (called the Lagrangian Schema[1]). While Ken did sign off on my use of these quotes, I wasn’t entirely fair to the Price & Wharton program because I didn’t reveal their…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6270 post-loop-21 post-parity-odd blog-grid with-slider post-6270 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-block-universe tag-block-world"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Blockworld and its Foundational Implications: Delayed Choice and No Counterfactual Definiteness" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-5-delayed-choice-no-counterfactual-definiteness/" rel="bookmark" title="Permanent Link: Blockworld and its Foundational Implications: Delayed Choice and No Counterfactual Definiteness">Blockworld and its Foundational Implications: Delayed Choice and No Counterfactual Definiteness<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-10T13:17:24-06:00" >November 10, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  In parts 1 and 2 of this 5-part Insights series, I explained the blockworld (BW) implication of special relativity. In part 3, I introduced general relativity (GR) and brought BW to bear on general relativistic cosmology to ‘explain’ what puzzles so many people about big bang cosmology, i.e., the origin of the universe. The bottom…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6245 post-loop-22 post-parity-even blog-grid with-slider post-6245 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-block-universe tag-block-world"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Blockworld and its Foundational Implications: General Relativity and Closed Timelike Curves" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-4-general-relativity-closed-timelike-curves/" rel="bookmark" title="Permanent Link: Blockworld and its Foundational Implications: General Relativity and Closed Timelike Curves">Blockworld and its Foundational Implications: General Relativity and Closed Timelike Curves<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-09T21:38:34-06:00" >November 9, 2015</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-4-general-relativity-closed-timelike-curves/#comments" class="comments-link" >2 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  In parts 1 and 2 of this 5-part Insights series, I explained the blockworld (BW) implication of special relativity (SR). In part 3, I introduced general relativity (GR) and brought BW to bear on general relativistic cosmology to ‘explain’ what puzzles so many people about big bang cosmology, i.e., the origin of the universe….</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6181 post-loop-23 post-parity-odd blog-grid with-slider post-6181 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-block-universe"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Blockworld and its Foundational Implications: General Relativity and the Big Bang" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-3-general-relativity-big-bang/" rel="bookmark" title="Permanent Link: Blockworld and its Foundational Implications: General Relativity and the Big Bang">Blockworld and its Foundational Implications: General Relativity and the Big Bang<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-09T00:24:54-06:00" >November 9, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  In parts 1 and 2 of this 5-part Insights series, I explained the blockworld (BW) implication of special relativity (SR). Geroch sums up the BW perspective nicely with this quote[1]: There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. In particular, one does not think of particles as…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6149 post-loop-24 post-parity-even blog-grid with-slider post-6149 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-block-universe"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Blockworld and Its Foundational Implications: The Relativity of Simultaneity and Blockworld" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-2-relativity-simultaneity-blockworld/" rel="bookmark" title="Permanent Link: Blockworld and Its Foundational Implications: The Relativity of Simultaneity and Blockworld">Blockworld and Its Foundational Implications: The Relativity of Simultaneity and Blockworld<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-06T15:18:50-06:00" >November 6, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  In part 1 of this 5-part Insights series, I introduced two consequences of the second postulate of special relativity (SR): time dilation (“moving clocks run slow”) and length contraction (“moving objects shrink”). Since moving clocks run slow, if you and observers at rest with respect to you (hereafter simply “you”) see me moving, you…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6093 post-loop-25 post-parity-odd blog-grid with-slider post-6093 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-block-universe tag-block-world"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Blockworld and Its Foundational Implications: Time Dilation and Length Contraction" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/blockworld-foundational-implications-part-1-time-dilation-length-contraction/" rel="bookmark" title="Permanent Link: Blockworld and Its Foundational Implications: Time Dilation and Length Contraction">Blockworld and Its Foundational Implications: Time Dilation and Length Contraction<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-11-05T00:38:05-06:00" >November 5, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>  This is the first in a 5-part series of Insights that will introduce blockworld (aka “block universe”) and use it to address a puzzle (origin of the universe), paradoxes[1] (of closed timelike curves), and conundrums[2] (of quantum nonlocality) that I have seen discussed on Physics Forums. Blockworld (BW) says the past, present and future are equally ‘real’, i.e.,…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6734 post-loop-26 post-parity-even blog-grid with-slider post-6734 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-mechanics"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Weak Values Part 2: The Quantum Cheshire Cat Experiment" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/weak-values-part-2-quantum-cheshire-cat-experiment/" rel="bookmark" title="Permanent Link: Weak Values Part 2: The Quantum Cheshire Cat Experiment">Weak Values Part 2: The Quantum Cheshire Cat Experiment<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-05-30T14:55:00-05:00" >May 30, 2015</time><span class="text-sep">/</span><span class="comment-container minor-meta"><a href="https://www.physicsforums.com/insights/weak-values-part-2-quantum-cheshire-cat-experiment/#respond" class="comments-link" >0 Comments</a></span><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In a previous Insight, Weak Values Part 1: “Asking Photons Where They Have Been,” I showed different methods for computing the relative intensities in the weak measurements done by Danan, Farfurnik, Bar-Ad, and Vaidman (DFBV)[1]. In that experiment, DFBV had a weak transverse signal, created by mirrors oscillating with small amplitudes transverse to the beam path through an interferometer, piggyback…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6515 post-loop-27 post-parity-odd blog-grid with-slider post-6515 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-retrocausality"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Weak Values Part 1: Asking Photons Where They Have Been" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/weak-values-part-1-asking-photons/" rel="bookmark" title="Permanent Link: Weak Values Part 1: Asking Photons Where They Have Been">Weak Values Part 1: Asking Photons Where They Have Been<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-05-30T14:53:16-05:00" >May 30, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In a previous Insight on retrocausality, I explained an experiment by Danan, Farfurnik, Bar-Ad, and Vaidman (DFBV)[1], “Asking Photons Where They Have Been” using various retrocausal models. In this Insight, I will give a brief introduction to the formalism for computing the relative power spectra in that experiment. Specifically, I will show how the weak…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6986 post-loop-28 post-parity-even blog-grid with-slider post-6986 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-experiment"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: Learn About the Greenberger-Horne-Zeilinger Experiment" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/greenberger-horne-zeilinger-experiment/" rel="bookmark" title="Permanent Link: Learn About the Greenberger-Horne-Zeilinger Experiment">Learn About the Greenberger-Horne-Zeilinger Experiment<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-05-09T06:13:27-05:00" >May 9, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In two previous Insights, I shared Mermin’s explanation of the Hardy experiment[1] and the Mermin device[2]. Both of his corresponding AJP papers presented nontechnical arguments against “instruction sets” aka “counterfactual definiteness” for quantum mechanics (QM). In the case of the Mermin device, Elitzur & Dolev showed a particular experimental instantiation yielded a quantum counterpart to the liar paradox[3]. Herein I will share a third Mermin AJP paper[4]…</p></div></div><footer class="entry-footer"></footer></article><article class="'post-entry post-entry-type-standard post-entry-6858 post-loop-29 post-parity-odd post-entry-last blog-grid with-slider post-6858 post type-post status-publish format-standard has-post-thumbnail hentry category-physics-articles tag-quantum-experiment"' itemscope="itemscope" itemtype="https://schema.org/BlogPosting" itemprop="blogPost" ><div class="entry-content-wrapper clearfix standard-content"><header class="entry-content-header" aria-label="Author Archive Post: The Quantum Liar Experiment: An Instantiation of the Mermin Device" ><h2 class='post-title entry-title ' itemprop="headline" ><a href="https://www.physicsforums.com/insights/quantum-liar-experiment-instantiation-mermin-device/" rel="bookmark" title="Permanent Link: The Quantum Liar Experiment: An Instantiation of the Mermin Device">The Quantum Liar Experiment: An Instantiation of the Mermin Device<span class="post-format-icon minor-meta"></span></a></h2> <span class='post-meta-infos'> <time class="date-container minor-meta updated" itemprop="datePublished" datetime="2015-05-09T06:12:35-05:00" >May 9, 2015</time><span class="text-sep">/</span><span class="blog-categories minor-meta">in <a href="https://www.physicsforums.com/insights/science-math-articles/physics-articles/" rel="tag">Physics Articles</a></span><span class="text-sep">/</span><span class="blog-author minor-meta">by <span class="entry-author-link" itemprop="author" ><span class="author"><span class="fn"><a href="https://www.physicsforums.com/insights/author/ruta/" title="Posts by Mark Stuckey" rel="author">Mark Stuckey</a></span></span></span></span></span></header><div class="entry-content" itemprop="text" ><p>In 1981, Mermin published a paper[1], “Bringing home the atomic world: Quantum mysteries for anybody” in which he explained the mystery of quantum nonlocality[2] without requiring the formalism of quantum mechanics (QM). I will summarize that argument then show how the QM formalism fits his results and how his device is instantiated in Elitzur & Dolev’s quantum liar experiment (QLE)[3]. The quantum state…</p></div></div><footer class="entry-footer"></footer></article></main><aside class='sidebar sidebar_right smartphones_sidebar_active alpha units' aria-label="Sidebar" role="complementary" itemscope="itemscope" itemtype="https://schema.org/WPSideBar" ><div class="inner_sidebar extralight-border"><section id="custom_html-2" class="widget_text widget clearfix widget_custom_html"><div class="textwidget custom-html-widget"><h2 class="widgettitle">Trending Articles</h2><ul class="wpp-list wpp-sunset"><li class="" style="--item-position: 1;--total-items: 10"><div class="item-position"></div><div class="item-data"><a href="https://www.physicsforums.com/insights/hand-wavy-discussion-planck-length/" class="wpp-post-title" target="_self">What Planck Length Is and It’s Common Misconceptions</a></div></li><li class="" style="--item-position: 2;--total-items: 10"><div class="item-position"></div><div class="item-data"><a href="https://www.physicsforums.com/insights/can-see-atom/" class="wpp-post-title" target="_self">Can We See an Atom?</a></div></li><li class="" style="--item-position: 3;--total-items: 10"><div class="item-position"></div><div class="item-data"><a href="https://www.physicsforums.com/insights/the-7-basic-rules-of-quantum-mechanics/" class="wpp-post-title" target="_self">The 7 Basic Rules of Quantum Mechanics</a></div></li><li class="" style="--item-position: 4;--total-items: 10"><div class="item-position"></div><div class="item-data"><a href="https://www.physicsforums.com/insights/pbs-video-comment-what-if-physics-is-not-describing-reality/" class="wpp-post-title" target="_self">PBS Video Comment: “What If Physics IS NOT Describing Reality”</a></div></li><li class="" style="--item-position: 5;--total-items: 10"><div class="item-position"></div><div class="item-data"><a href="https://www.physicsforums.com/insights/what-is-a-tensor/" class="wpp-post-title" target="_self">What Is a Tensor? 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