radioactivist

11 ms·

61.
by radioactivist 5y ago
This is true, though there is there is one strong philosophical reason to prefer accounting for the energy as being stored in the fields themselves: it makes the theory "local". I.e. for energy to go from A to B it's got to t
62.
by radioactivist 5y ago
That paper is not anything really. Their "formula" for the electron mass is a combination of some Planck units the fine structure constant and the Bohr radius. But the Bohr radius is defined in terms of the electron mass -- and if
63.
by radioactivist 6y ago
One hundred years ago there were many things that did not have any real explanation -- classical physics was not "stuck" and was not "explaining everything fine". Our understanding of something as common as metals and in
64.
by radioactivist 6y ago
If you're already 75 years old your life expectancy is roughly another 10 years (COVID deaths skew to the 70+ age bracket). So I'd expect the "deficit" in deaths to be spread out over at least 5-10 years. This might not
65.
by radioactivist 6y ago
I think it's that a score of >90 means the result is within the error bars of whatever particular experiment was chosen to be the "reference".
66.
by radioactivist 6y ago
One thing I found interesting about the final polling averages was that they were much more correct about Biden's share of the vote, even when they were very wrong about the margin itself (since these polls don't add to 100%, th
67.
by radioactivist 6y ago
A uniform force doesn't do anything harmful to you. You get stretched into spaghetti by the difference in force between the ends of your body. In large black holes that difference can be small even as you pass through the horizon (wher
68.
by radioactivist 6y ago
Yes, those are both possibilities for building a polarizer [1]. For example, a simple polarizer could be a grid of thin metal wires whose spacing is smaller than the wave-length of the incoming light. For the component of the E-field parall
69.
by radioactivist 6y ago
The article/your video make the assumption that light is particle and that those particles are independent and each carry polarization. While we know those assumptions to be true, the classical theory of light is not a theory of partic
70.
by radioactivist 6y ago
While this is a nice demonstration of the polarization of light, this is not a demonstration of quantum mechanics, or quantum computing (though it does have pedagogical value, if qualified properly). Polarizers essentially just project the
71.
by radioactivist 6y ago
Yes, the point that is often missed is that Coulomb interactions aren't enough on their own.
72.
by radioactivist 6y ago
This is generally true for anything to do with matter at the microscopic level: not just chemistry, but many things about things like insulators, metals and other solids just don't make sense without quantum mechanics. Even in the stab
73.
by radioactivist 6y ago
There is also the Poynting Vector [1] named after John H. Poynting [2] that "points" in the direction that electromagnetic energy is flowing. [1] https://en.wikipedia.org/wiki/Poynting_vector [2] https:&#x2F
74.
by radioactivist 6y ago
Most of the properties of materials are from the charged pieces that make them up -- the protons and electrons. Since adding neutrons wouldn't change the number of electrons or protons other isotopes would be almost identical for the p
75.
by radioactivist 6y ago
> Ok, but isn’t the premise of this line of reasoning flawed? We didn’t know what our understanding of electromagnetism and quantum mechanics would enable in advance. No, but we did know what we had large gaps in our knowledge, even of t
76.
by radioactivist 6y ago
I agree the distinction can get a little fuzzy at the edges, i.e. for technologies that, while not dependent on frontier physics, would only have been developed in the pursuit of (say) building a larger collider. But I think there is a real
77.
by radioactivist 6y ago
Sorry, I didn't realize how nested this had gotten; this statement: > One would argue that modern electronics are possible because research was done about Quantum Physics, a fundamental nature of reality. which was making the connec
78.
by radioactivist 6y ago
If that's the reason one wants to continue funding particle accelerators -- and it's a good argument -- then one needs to make precisely that argument (and not the argument made a few levels up by the original poster).
79.
by radioactivist 6y ago
You're probably right that my statement about "indirect" applications was a bit strong. I agree that there are numerous applications some fairly direct (like medical physics) and some very indirect (like the WWW) that have co
80.
by radioactivist 6y ago
Thank you for expanding on this -- I agree with all of these points. There is a real and tangible, albeit in this case indirect, value to have highly skilled people try to push that boundaries of what is possible technologically. It is easy
81.
by radioactivist 6y ago
I don't know of any promising prospects. I think nuclear physics provides an instructive example that sits in between some of these extremes. Here the energy scales are way way lower than current frontier standards, but also fairly div
82.
by radioactivist 6y ago
The experimental platforms that I am aware of that are been used to try and build quantum computers are based on condensed matter physics (superconducting junctions), atomic physics (trapped ions) or photons (quantum optics). None of this i
83.
by radioactivist 6y ago
While I sympathize with this viewpoint, as a physicist I think there is a fairly persistent misunderstanding in the public about just how disconnected current particle physics experiments are from application to everyday life. Essentially n
84.
by radioactivist 6y ago
While I agree the article doesn't properly contextualize the number, that's not really the right comparison. Alameda county has had 2564 cases in total since March (up to May 20th) -- so you'd have expected 15 employees to ha
85.
by radioactivist 6y ago
Helium does not solidify down to the lowest temperatures that have been achieved (at standard pressure). Though it does become a superfluid, which is a distinct phase of matter from a gas/liquid.
86.
by radioactivist 6y ago
This is true, but doesn't have anything to do with quantum mechanics -- the third law of thermodynamics is basically a statement that you can't cool things to absolute zero.
87.
by radioactivist 6y ago
That study (and the related Santa Clara study by a subset of the same authors) were torn apart by statisticians for the shoddy methodology and irresponsible selling of its results to the media.
88.
by radioactivist 6y ago
They are now including many of the suspected (but untested) cases in their reported numbers now. It increased the total from New York by a significant amount, see [1]. The increase is roughly in line with similar estimates from excess morta
89.
by radioactivist 7y ago
https://youtu.be/rqFMbXMfS9Q
90.
by radioactivist 7y ago
If the axis labels are correct (which, after referring to the full paper, they seem to be) then I think this is the only reasonable explanation. I.e. that the dataset tracks all authors of scientific publications, rather than those who ar

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