Slightly. Through FFRF. FFRF gave him an award for speaking at our convention and his work for nontheism. However FFRF has distance themself’s from him in light of the allegations. FFRF is a very pro-feminist group. While Dr. Krause remains in the penalty box, it is best to let the investigation continue without outside influence.
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Disclaimer: my field of specialization is experimental tests of fundamental physics. I’m not an expert on string theory nor GR. But let’s take Patrick’s example of quantum mechanics, or to be more precise and up-to-date, the Standard Model (SM) of particle physics. The SM is a framework that incorporates three of the four kinds of forces we know in the universe: electromagnetism, strong, and weak forces. The SM gives some meaning to the fundamental particles we know of in the universe (e.g. electron, muon, 6 types of quarks that make up protons and neutrons) as well as the particles that mediate forces (photons, gluons, and gauge bosons). It is completely harmonized with quantum mechanics (QM) and special relativity (SR). But It does not say anything about gravity or General Relativity, the theory which we use to describe gravity.
Now does the SM contradict evidence? Yes and no. Patrick is right in that the SM has passed almost every experimental test that we’ve thrown at it.* The Higgs boson was discovered in 2012, the last piece of the SM. Since then the Large Hadron Collider (LHC) has kept running at higher energies and so far we’ve not discovered any new, exotic particles not predicted by the SM. The most precise measurement in all of physics is predicted by quantum electrodynamics (QED), a part of the SM: the magnetic moment of the electron. In this case, theory and experiment have been shown to agree at 12 decimal places. (Incidentally, the experiment to show this was done downstairs in my lab at Harvard.) Because of this incredible robustness, one can say that the SM is the crowning achievement of decades of particle physics from the 1950s to 2012.
But there are several problems with the SM. One of the biggest ones: according to the SM, the universe as we know it shouldn’t exist. The reason is because the SM doesn’t explain what makes antimatter different from matter. They are perfect opposites of each other. Thus, the Big Bang should’ve produced equal amounts of matter and antimatter, resulting in the two annihilating each other, giving us a bath of photons: no atoms, stars, galaxies, or planets. No us. Now is that an “empirical observation”? I surely think so. This problem is called baryogenesis: by what mechanism does nature produce the asymmetry of baryons verses antibaryons? Questions like these are what makes many particle physicists continue to test the SM, looking to see if it fails in any way. My own experiment is one of those. It looks to find something called CP violation which is not predicted by the SM, which might be the key to explaining baryogenesis. I’ve written more about this in my blog before, if anyone is interested to read it: Why CP Violation Might Explain Everything About the Universe.
So to sum up, while the SM has indeed passed most of the laboratory tests we’ve thrown at it, it fails to explain certain basic features of the Universe. All particle physicists desperately hope that the SM is false at some level. In fact some would go as far as to say we know it cannot be all there is, because of these issues.
- Caveat: Neutrino oscillations are not covered by the SM, and we know they exist. Because of that the people who discovered it got Nobel Prizes. But neutrino oscillations are not the smoking gun that will guide us into figuring out what is wrong with the SM, because one can incorporate them into the SM by a very simple extension to the model. In other words, it’s not weird enough. There was a recent neutrino result regarding sterile neutrinos which might make my statement outdated (and I am not a neutrino expert), but that experimental result has not been unanimously accepted by the community, AFAIK.
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dga471 - glad you are here. I name you our physics expert. Thanks for this explanation of the cutting edge in physics. Welcome, we are a friendly group, quarky at times, but usually thoughtful, inquisitive and caring of one another in a humanist kind of way. We are suppose to be about discussing science peacefully but we digress into a little of everything all the time. The person who makes it all work is Dr. Swamidass, a physican, a tenured assistant professor at WUSTL and an active researcher in computational biology. (Did I get that right?) He is also a fine human being.
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An additional important point about the SM that I missed: the SM doesn’t explain dark matter. Dark matter is a form of matter that interacts gravitationally but not electromagnetically (thus “dark” - we can’t see it directly using telescopes). We have very strong evidence that dark matter exists through astronomy. The most famous one are anomalies in galaxy rotation curves discovered by Vera Rubin in the 1970s. The only plausible explanation was that these galaxies contained a large mass of unseen matter other than what we could observe. Thus the wild hunt began to look for such matter, that continues to this day. All the candidates for dark matter are things that are not found in the SM: exotic particles that interact in a very different way compared to everything we’ve observed so far. Thus, people set up experiments such as LUX, which is literally a gigantic tub of xenon, with many detectors inside the tub. The idea is that if a hypothetical dark matter particle of a certain type that would interact well with xenon passes through, it would generate some photons that are picked up with the detectors. Unfortunately, none of these experiments have found anything. The search continues.
Thus, if exotic particles were found, we potentially are killing two birds with one stone: 1) they might explain what dark matter is, and 2) they might also shed light on other puzzles in the SM such as baryogenesis.
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This is great. Thanks for coming on. Can I ask a question? My quantum electronics training in the 1980’s was that the electron was a point charge of zero size. You are measuring the dipole moment which I understand implies that the electron has a physical size or radius. Can you explain what is today’s understanding of the size of an electron. Thanks.
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I think you are asking the right person. I do believe that this is what @dga471 engages in his scientific work.
I’m curious to hear how @dga471 corrects our ignorant musings.
Thanks for the welcome, Patrick!
I have been following Josh’s blog and this discussion forum for a few months now, and found it to be an incredibly insightful in the various debates about creation. In fact, when I first read Josh’s article about the genealogical Adam, everything just clicked within the first few sentences - I always knew in the back of my mind that as you go back, the number of ancestors one has multiplies exponentially - so why can’t any one of them be the historical Adam? Anyway, it was an incredible pleasure for me to meet @swamidass just this past weekend at the annual conference of the American Scientific Affiliation:
I hope to be able to learn a lot about biology, genetics, and other fields of science and their relation to theology by taking part in this discussion forum. I’m also looking forward to contributing a few little things I know about physics, when needed!
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me too. I feel like a dinosaur in this area now. I was once right at the cutting edge of this science - quantum electronics. Was measuring zero point energy of photons/electrons everyday. More of a nuisance noise than anything else. Going to feel like a jerk if that zero point energy turns out to be the dark energy of the universe.
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You are correct that in the Standard Model, the electron is a fundamental particle and is thus regarded as a point particle with zero physical size. (Before quantum mechanics, one could calculate the so-called classical radius of the electron, which is non-zero, but this is only used for illustration purposes and is not our best theory of the electron.) What my experiment is measuring is not the physical size, but the electric dipole moment (EDM) of the electron - how symmetric its charge distribution is. If it is completely symmetric - i.e. forming a perfect sphere, then we would call it a perfect monopole. If it is slightly squishy - i.e. slightly resembling a dipolar object, like a magnet with north and south poles - then it would have a non-zero EDM. Thus, the EDM of an electron is a measure of the “squishiness” of the electron’s charge distribution. One can examine this property by subjecting the electron to a very strong electric field and see how it behaves.
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okay a perfect sphere of radius zero. Yep that what I remember. Made perfect sense 40 years ago and now. 
That is what I love about quantum mechanics. I am trying to stay up on quantum computing, quantum cryptography and quantum entanglement. Progress is amazing.
You are measuring a perfect sphere of charge, and not a perfect sphere of matter. Right?
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The best way I understand wave-particle duality is that everything is either a particle or a wave depending on what you’re doing to it and how you’re looking at it. The wavelength of anything can be calculated using the de Broglie formula : lambda = h/p, where h is Planck’s constant and p = mv is the momentum of the particle. (Note: wish we could turn on LaTeX on this forum!)
Because h is such a small number, the wavelength of most massive things is very small, so in everyday life nothing you regularly encounter can make you experience massive particles as waves. But experiments have been done to show that things such as electrons do act like waves in the right conditions. In 1927, the Davisson-Germer experiment found that electrons do behave like waves in that they exhibit a diffraction pattern when they bounce off a target. This vindicated de Broglie’s theory and won him the Nobel Prize. So yes, the electron can still be considered a wave, just like everything else, and it does “occupy the whole universe.”
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Pilot theory of particles and waves is that there is a particle riding on a wave… possibly involving additional spatial dimensions.
The “radius zero” part is not quite right. Think of it like this: a perfect sphere charge distribution means that the electric field you experience around an electron at a certain distance R is the same, regardless of your angular position around the electron. I.e., the charge distribution depends only on the radius and not the angles theta or phi (assuming spherical coordinates).
It depends on what you mean by “matter”, as the electron is certainly considered “matter”, even if it is a point particle with radius zero. Charge is a property of particles of matter, not something that can exist on its own. The electron is a charged particle. I would rather put it this way: we are trying to measure the geometry of the electric field produced by a charged particle, namely the electron.
(Are electric fields “matter”? Are fields in general “matter”? Do fields even really exist, or are they just calculational tools that physicists use to describe interactions? These are all more philosophical rather than strictly physics questions.)
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I think I understand. Thanks. And yes fields exists as I can measure them easily and they exert force
It’s almost as if you are saying the electric field is the electron…
How do you know it’s not one big universe wide electric field observable at specific points given certain conditions…
The electric field is not the electron. For once, we know that the electron has other properties, such as magnetism, that are different from its charged nature. The electron also has a mass.
The electric field of any electron does extend to the whole universe. However, because electric fields scale as 1/r^2, where r is the distance from the source (the electron), at large distances you will not be able to detect the field any more.
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Yes, the electron is spinning so has a magnetic field also and a polarity N/S poles. All this with zero radius.
Entangle two electrons, separate them thousands of mile. When I measure one, I know the other instantly.
Another point, which I heard discussed before regarding the “size” of the electron. As I said before, the electron is regarded as a point size particle in the Standard Model. But this assumption, too, has been tested in actual experiments. In other words, it could be the case that there is beyond-SM physics that results in the electron being a non-fundamental particle, having constituents of some unknown more fundamental particle. If that is the case, then one would be able to say it has a non-zero radius, similar to the proton, which is made of quarks bound together in some spatially extended state.
One of the experimental investigations for the radius of the electron has come from the measurement of the electron magnetic moment: Limits of Electron Substructure. In this case, the incredible agreement between theory and experiment within the framework of the SM which I mentioned above puts an upper limit on the radius of the electron: R < 10^-18 m. Other scattering experiments have constrained it even further to below 10^-20 m. So again, as far as we know from lab experiments, the SM is correct and we can treat the electron as a point particle.
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Since this topic got bumped, I might as well add something. Is Quantum Mechanics in conflict with Relativity? If you take relativity theory to imply that no causal influence can propagate through space faster than light, then yes, they actually are in conflict. This is the main implication of Bell’s theorem, as Bell himself understood it.