71–80 of 167 posts
Since I read the story "The Road Not Taken" from Harry Turtledove, I cannot stop thinking that we might eventually discover that the question of the conflict between the general relativity and quantum theories is something so simple and elegant that we never even considered it before.
I choked on this part: > The discussion recalls a messy, largely forgotten episode from the dawn of the quantum era. In 1905, Einstein interpreted experimental data to mean that light is “quantized,” coming in discrete particles now called photons. Others, including Niels Bohr and Max Planck, thought that the classical, wave nature of light might still be saved. [...] Most physicists presume that everything in the wo…
Earlier quoted context omitted.
Yes. The Standard Model has completely explained all experiments involving them for around 50 years now. In fact the outstanding success of the Standard Model has posed its own problems - the lack of deviations from it makes it hard for experiments to point in a useful direction for better theories to be developed along.
That's not quite accurate. There are a few things that the Standard Model doesn't exactly account for--neutrino oscillation being the most famous. The trouble is that these issues aren't really big enough to suggest new physics, and the experiments aren't good enough to really suggest how much patching actually needs to be done.
So I thought gravity was basically the curvature of spacetime. But if there's a "gravity" particle, those two things seem mutually exclusive? Can someone who understands this please explain it to me, thanks!
Our ability to solve integrals is much more limited when the dx represents a slight change in a function, rather than a small change in a real number. As a result, a lot of things that are easy to say in English such as "quantized curvature in spacetime," or "strongly coupled gauge theory," turn into a big mess when they're written down more precisely. One of the consequences of this limitation is that we have a mode…
I disagree with that part. For the strong force we have the "gluons" and they are considered particles and they have a strong self-interaction. The strong self interaction makes it a huge mess and a lot of things that involve gluons are impossible to calculate.
It's more like:
fake quote> Let's pretend for 30 minutes that the strong field don't self-interact, so we have this nice particles call gluons. Now we add this interaction to the Lagrangian to make gluons interact with other gluons, and now we have a problem.
I agree that that when gravity is small enough, then gravitons give an easy to calculate aproximation. IIRC at high enough energies calculations with gluons get not impossible to calculate too.
Earlier quoted context omitted.
This needs to be emphasized more, by the TFA too — most (theoretical) physicists think that detecting gravitons is an engineering exercise that has no implications* for quantum gravity (as understood by the public) >The model of non-self-interacting gravity is a particle we call a "graviton," This needs to be emphasized even more, because it has >when the dx represents a slight change in a function *see the discussio…
Because they don’t want to run the risk of being wrong, eh?
Physicists love to be wrong! If there is an experiment that disagree with the current theory, then is like the will west and everyone can publish their own pet theory that "fix" it. It's like raining free paper for them, their graduate students and everyone. Also, it's fun!
When experiments and theory agree, they have to use imagination to get a new "interesting" tweak that can be published. In some case the the tweak may be interesting, but most of the times it's not.
I remember a talk about a 2-sigma "particle". There was a small disagreement in some experiment, so someone did a thesis about a possible fix adding a new particle. A lot of hard work and hard calculations. It was a nice talk, and someone asked what what happened then. The sad new was that later the 2-sigma disappeared, it was only a fluke :( . This kind of work is important, but it's more boring that looking for new particles.
Earlier quoted context omitted.
That's not quite accurate. There are a few things that the Standard Model doesn't exactly account for--neutrino oscillation being the most famous. The trouble is that these issues aren't really big enough to suggest new physics, and the experiments aren't good enough to really suggest how much patching actually needs to be done.
Also the unexpectedly large mass of the Higgs, which suggested (to string theorists), super symmetry. Which unfortunately turned out to not exist unless it’s at some configuration that’s quite different from what was suggested
https://home.cern/news/news/physics/incredible-lightness-hig...
I choked on this part: > The discussion recalls a messy, largely forgotten episode from the dawn of the quantum era. In 1905, Einstein interpreted experimental data to mean that light is “quantized,” coming in discrete particles now called photons. Others, including Niels Bohr and Max Planck, thought that the classical, wave nature of light might still be saved. [...] Most physicists presume that everything in the wo…
I choked on this part: > The discussion recalls a messy, largely forgotten episode from the dawn of the quantum era. In 1905, Einstein interpreted experimental data to mean that light is “quantized,” coming in discrete particles now called photons. Others, including Niels Bohr and Max Planck, thought that the classical, wave nature of light might still be saved. [...] Most physicists presume that everything in the wo…
It’s understandable that you don’t like the desensitization of war that comes from our over usage of the word. Perhaps it speaks to a defect in American culture but this is how we communicate in our language. I think Arabic has too much emphasis on allah related phrases. But that’s how they speak. Nothing I can do about it. I don’t think said usage implies anything about their writing abilities.
Earlier quoted context omitted.
A graviton is the smallest possible unit of a gravitational wave. The amplitude of the wave corresponds to the number of gravitons, like you said, and its frequency to their frequency (quantum particles have frequencies that are related to their momenta). We're aware that light, at least, works like that.
A gravitational wave requires an event like a black hole merger, or basicially somerhing to move and change the field, right? In this case, how does the fact that a big object is still influencing space/time around it communicate that fact when it is not moving. Is that still gravitrons?
Assuming our guess about quantum gravity are correct, the normal gravitation force use gravitons too, they are virtual gravitons but the distinction between "real" and "virtual" particles is another whole can of worms.
Since I read the story "The Road Not Taken" from Harry Turtledove, I cannot stop thinking that we might eventually discover that the question of the conflict between the general relativity and quantum theories is something so simple and elegant that we never even considered it before.
Or, something like the simulation hypothesis is real and different models of reality are used at different length scales and the overlap is fuzzy.