Recent content by PeroK

A FBD is reliable technique for a problem like this. Especially as the problem has been presented as something tricky and possibly counter-intuitive. Those are precisely the problems where it's best to fall back on tried and trusted techniques.

There was this thread recently: https://www.physicsforums.com/threads/questions-about-schwarzschild-cosmology-and-white-hole-big-bangs.1086165

The Big Bang starts from a "hot, dense" state. This is not the science-fiction forum!

Why is one not appropriate in this case? That's what I used.

I just looked at this. We have a force of magnitude ##F_1## applied to the left (backwards). This, through the gearing mechanism, also produces a clockwise torque on the back wheel of ##\tau_1 = rF_1##, where ##r## is a gearing factor, with dimension of length. The friction between the back...

I apologise if I misunderstood what you were saying.

Yes, but the blip on the screen is just a blip. It could mean anything. There is nothing inherent in a blip to distinguish one phenomenon from another. It might be a heartbeat; it might be a muon detection; it might be an increase in a share price on the stock market. An animal is limited by...

We know about things beyond our senses. UV and IR light. Electrons, atoms, molecules; chemistry. We are able to go beyond our senses. Modern physics is not the physics of our senses. The quark model, for example. Likewise, mathematics goes beyond anything that can possibly be mapped onto...

To summarise: Children don't have to solve Zeno's paradox in order to run. Likewise, we don't have to derive all mathematics rigorously before we can do it. Otherwise, there would be no maths before Russell and Whitehead. How did Euler do mathematics without ZFC? I don't think this is true...

That's true, but we can and do introduce the concept of the infinite set of natural numbers without any philosophical difficulties. Even at the high school level, you are faced with this question. Does it makes sense that the natural numbers go on forever; or, do we have to stop at some point...

Where did philosophy help with the development of the COVID vaccine (or any vaccine)? You do an experiment to disprove something in science. This is a fundamental difference between science and philosophy. "If it doesn't match experiment, it's wrong. It doesn't matter what your name is or...

Modern physics has freed itself from the shackles of religion and philosophy! What was the philosophy behind the COVID vaccine? Was that worthless science?

I don't understand this type of thinking. It's a bit like asking what's the difference between chemistry and biology? Or, what's the difference between chili con carne and a cheeseburger? I can personally find no insight in comparing mathematics and physics. Instead, understand physics for...

In general, a computer system (AI or otherwise) would need additional functionality to explain it to humans. For example, a chess engine finds the best moves. But, it's very different to explain them to a human. A mathematical proof is similar. There is the line by line proof, but an...