swansont

It's not just mirrors. A heated gas will not give you a population inversion, which is a requirement for lasing. A neon tube won't lase without adding helium, so you can get He excitations by electron collisions and transfer of this excitation energy to the neon. More importantly, this has nothing to do with laminar flow.

citation needed.

I think it’s accurate to say physicists* use some vocabulary that doesn’t mean what a lay use of those words mean. Physicists also use jargon, because they understand what the jargon means, and in both cases if you hear the discussion without an appreciation for this, you will not get the same message. So yes, physicists might speak differently to a lay audience, for fear of being misunderstood. *(true of all scientists, not just physicists)

The gymnastics was constrained by math and (in part) existing theory, which was supported by evidence.

Can you post the info here, so we don’t have to wade through a video?

You didn’t explain why your numbers are physically relevant.

To this I would add that even if one person thinks a particular model is reality (especially if its their theory), it doesn’t mean that this is true of all of physics. “this bit is real” says nothing about the rest. (plus all the counterexamples, of course)

You mentioned antigravity, and cited a fifth force as if it were an accepted thing. You agree that expansion is not a force, so your question/comment makes no sense, because you refer to it as a force. You can’t have it both ways. Expansion adds space between two objects, so they move apart, even if locally there is no motion. Space doesn’t exert a force on them. They don’t move apart if they are gravitationally bound, because space doesn’t exert a force on them.

I’m not sure “preference” tells the story here. It’s where the ideas led him. A spinning wheel’s circumference can’t be described by 2pi*r owing to length contraction leads you to a non-Cartesian system. Add to this the notion that don’t feel gravity in freefall, you feel a force of something else when you aren’t in freefall, leads you to the idea that being stationary in a gravitational field is the accelerated frame.

The original question was (emphasis added) “Anyway, the question in short: Is gravity a force or not? (In layperson's terms, insofar as possible)”

Good. Now please explain what you mean by the fifth force, and why you phrased it as if this were mainstream physics.

What are you saying is the fifth force? The mainstream interpretation is that it’s speculative. In physics, there are four observed fundamental interactions (also known as fundamental forces) that form the basis of all known interactions in nature: gravitational, electromagnetic, strong nuclear, and weak nuclear forces. Some speculative theories have proposed a fifth force to explain various anomalous observations that do not fit existing theories https://en.wikipedia.org/wiki/Fifth_force Expansion of space is not a force. Matter feels no acceleration from space being added between it and other matter. i.e. it acts on space. Dark energy gives us acceleration of expansion, not the expansion itself.

If that were the case then you’re reiterating a point that’s been made several times, and studiot spoke of the force of gravity, putting us in the Newtonian realm, so I figured that can’t be it.

Gravity isn’t a force in GR, so this is moot. In Newtonian terms, something in freefall is still experiencing a force - it’s accelerating.

How is this 0.9fs a “pulse”? You have a proton traveling 30m, which is an arbitrary distance. What’s the connection to the radiation emitted? Is this radiation observed in linear accelerators? Please provide evidence.

What leads you to this conjecture? There is no fifth interaction in mainstream physics.

But that’s not the case. Expansion occurs where gravity is too weak to stop it, but that’s not the same thing as no gravity, as you acknowledged earlier. Frankly, this does not seem to be a difficult concept; the concepts of motion and force it evokes are Newtonian. If gravity in a region is strong enough to prevent expansion, that’s what happens.

The OP asked a physics question (which was answered) so there’s no reason to relocate it. You might be thinking of a question asked in a later post.

Charges undergoing acceleration (e.g. via collisions) will emit photons

! Moderator Note Several of your posts are assertions. If you stick to asking questions, there isn’t a problem. But e.g. “Because sound waves have anti gravity properties” is not a question

Where is your calculation that shows the wavelength?

All inertial observers are at rest in their own frame, so saying two observers are at rest does not fully specify that they are at rest with respect to each other. We can be moving with respect to each other and each claim to be at rest. So as zapatos notes, rest (and motion) always has to be specified with respect to something.

Already did, in 1905 https://en.wikipedia.org/wiki/Jacobson_v._Massachusetts The Supreme Court reaffirmed its decision in Jacobson in Zucht v. King (1922), which held that a school system could refuse admission to a student who failed to receive a required vaccination

The basic idea in relativity is that one observer notices time dilation and another observer notices length contraction. This is how they reconcile the speed of light being the same. A lab observer sees the electron’s clock running slow, and the electron “sees” its path as being shorter. That reconciles (qualitatively, at least) each noticing more distance traveled in a span of time, and the frequency going up as the energy increases, even though the speed doesn’t change much.

They must be at rest with respect to each other to be in the same frame