Recent content by Ralph Dratman

@Jarvis323 Your request for formalization is spot on. "What is a simulation, and how is it different than a non-simulation?" That is the exact kind of question that needs to be asked in this, as in many "philosophical" problems. For example, long discussions of free will should be prefaced with...

That is a much better way of looking at it!

Thanks very much for that information! I didn't know there was some feeling that the values of the physical constants were a problem. And Sabine Hossenfelder is adding fuel to that fire? I will have to find that video if she has one. I watch her from time to time. (I personally often go to Las...

It is not even a(n) hypothesis unless it has specifics.

My point is that vague speculation is not a scientific theory.

In order for any kind of computer to simulate our universe, the computer would have to exist in a "real" universe at least several times larger than our own. Well, it must be larger if we assume it takes more than one "real" atom to simulate a simulated atom, and also the computer would not...

I beg to differ. But don't take it to heart. Actually, I know you won't.

in actual history, when computers enter a new field, they have always helped people do their existing jobs. Actually replacing people is rare, as far as I can see. At worst, I suspect mathematicians will be enabled to spend more time asking challenging questions and combining new answers with...

I don't see the problem with some individual not believing something in physics. Anyone is free to disbelieve. Why not? I suppose one might worry that such an opinion could become widespread, something like vaccine rejection. Personally that does not worry me either, because disbelief in a...

I do not see how you could pull any kind of vacuum, good or bad, in something light enough to be used as the lifting body of an airship. It is the pressure of the hydrogen or helium in a rigid-body airship that keeps the lifting body from imploding, as it would if the gas were not there.

I agree with Ibix that the answer depends on what you take as "real" or "not real". Nevertheless I think I understand the motivation of the question, as I have often wondered whether, for example, a sharp click sound is "really" a combination of many different high frequency "tones" -- as the...

Great answer! What a fascinating thought.

There is a measurable 120 Hz flicker in US incandescent lighting, a stronger flicker at the same rate in fluorescent illumination, and a maximal on-off flicker in AC-driven LED light. However, the cyclic variation of brightness is too fast for most people to perceive without a device to count...

Could you please explain what you mean by "observer dependent"? Thank you.

To see the effects of time reversal in classical mechanics you just have to change the sign of all velocities -- that is, reverse their direction. In a gravity field the original, un-reversed falling object would be speeding up, falling faster and faster. Imagine you reverse the velocity. Now...