Recent content by Warp

Are you saying that if the speed of light is different in different directions, that's completely unobservable? Surely if light moved in one direction at c and in another direction at 1m per year, there would be some observable effect?

If the speed of light were different in different directions, couldn't this be observed in other ways, such as unexpected redshift/blueshift, or unexpected patterns in the cosmic microwave background radiation? (I know this isn't really related to my original question anymore, but anyway...)

Perhaps Rømer's experiment alone doesn't prove that the speed of light is the same in all directions, but if the result is the same as the two-way speed as measured in a different experiment, wouldn't this combination of two experiments prove it? Or would it merely prove that the one-way speed...

That doesn't matter. It doesn't matter where the light originates from, as that has zero effect on the measurement being made. Io could just as well be producing and emitting the light itself (eg. via some volcanic activity), and it would still give the exact same result.

So I understand from the responses that his experiment assumes that the speed of light is the same in all directions, and the result of the experiment is calculated using that assumption, but the experiment all in itself doesn't prove that the speed of light actually is the same in all...

I don't understand. The experiment doesn't rely on knowing what time the light left Jupiter. It relies on measuring how long Jupiter's moon traverses to the other side of the planet (as well as knowing the radius of Earth's orbit). It doesn't matter what the time is at Jupiter, what matters is...

I am not even allowed to briefly mention that I asked it the question and didn't fully understand its answer, which is why I'm asking here? Is this some kind of weird "He Who Shall Not Be Named" thing?

Some years ago the popular youtuber Veritasium made a video about how it's (at least seemingly) impossible to measure the one-way speed of light, and how no matter what you are trying to do, you'll always be measuring the two-way speed, even if your contrived example is trying to masquerade it...

Do I understand correctly that the air loses some potential energy and the arising balloon+object gains it? But now, if the object (let's say it's a metallic ball) is let loose from the balloon, it will fall down and release energy when it impacts the ground. In the atmosphere, however, not...

So... how does this manifest, exactly? Does the air get colder or something? What's the mechanism of energy transferral?

My thinking is that because of the law of conservation of energy, the amount of energy needed to raise an object to a certain altitude has to be at least as much as the amount of energy released by the object if it were to be dropped from that altitude and hit the ground (and all that released...

I was watching this YouTube video by the channel The Action Lab: At one point it shows this capillary tube phenomenon: It got me immediately thinking: Conservation of energy much? What's stopping that second tube from being bent into draining into the leftmost tube, thus creating an...

It's extremely hard, if not outright impossible, for our limited brain to visualize 4D objects. 3D objects are fine, but 4D is just impossible (except, maybe, to some people). However, at one point I figured out a way to comprehend (in some ways "visualize") the 4-dimensional hypercube, which...

I was conversing with ChatGPT when I asked which material has the highest melting point, and it answered "tungsten" (giving its melting temperature). It so happened that in the previous question the melting point of graphite had come up, and it was listed as higher than that. When I asked which...

When talking about this subject, terminology tends to be mixed up quite a lot, and the colloquial use of words tends to vary wildly from their strict physics-mathematical definitions. If someone says "gravitational pull is constant" you really have to ask for clarification of what exactly they...