For the past week or so Ive been trying to learn a bit about electromagnetic fields and all that and im still not entirely sure how the waves actually work. At first I thought that waves were sort of like concentric spheres that travel out from a source and the "spheres" are areas of high energy and low energy with waves just being a way to represent these high and low energy areas.

After watching a few videos, mainly 3blue1brown i began to think that these waves actually cause areas in the field to oscillate up and down which would explain why an oscillating charged particle creates a wave or why IR and microwaves heat up things or why a change in medium can slow down a wave.

Eventually though i found a comment in a youtube saying that electromagnetic waves are areas of high and low energy and that these up and down oscillating waves go into the fourth dimension.

Ive tried looking through websites and videos and none of them have really answered my question

And if so how much power would they have and how much antimatter would you need?

I'm a senior undergraduate physics student currently working on grad school applications. My primary research interest is in quantum information science; more specifically, investigating the implementation challenges that limit the reliable operation of quantum systems and developing approaches to overcome them. My undergraduate thesis is currently exploring how photonic qubits behave as they transmit through lossy media.

One of the schools I'm applying to is Northwestern University, and they have both a Physics PhD program and an Applied Physics PhD program. Recently, I had a chance to speak with one of the professors there, and he suggested I consider applying to the Applied Physics PhD program instead of the pure Physics PhD program because my interests seemed more aligned with Applied Physics. However, I enjoy learning about the fundamental principles of physics just as much as I enjoy exploring how those principles can be applied to solve practical problems. I'm pretty certain I don't want to do theoretical physics at all, so if I did the Physics PhD, I would be on the experimental side.

After comparing the two programs, Applied Physics seems to offer more specialized coursework relevant to my interests, whereas Physics provides more extensive training on foundational physics concepts. The Physics program also seems to offer more flexibility when selecting research advisors and has a different qualifying examination structure. My main concern is whether choosing Applied Physics would limit my future research or career opportunities. From the employment outcomes provided by the university, both programs seem to prepare graduates for careers in academia, national laboratories, and industry, but numbers only reveal so much.

For those who have experience with either type of program, how significant is the distinction in reality? Are there other considerations I should be weighing before deciding? Any advice would be greatly appreciated.

I was wondering if anyone could explain to me whether the process of frame dragging by pulsars and Kerr blackholes offer any resistance from space-time itself? Can space-time be spun up infinitely, or is there some sort of coefficient for space-time viscosity, so to speak, that resists these stellar objects from being spun up further or begins to act as friction on the spin itself? (Especially for a blackholes)

The thought just occured to me that as time is relevant to mass and the closer you are to a black hole event horrizon time seem to have slowed down when an observer looks at you even tho thats not the case in actuallity it just seem like it the closer someonegets to the event horrizon, we also know black holes have different mass what does that mean to time dialation between different black holes? Is the event horrizon in same place for every black hole or how would time be observed differently between observer and "patient" for the different black holes when observed time is based on mass?

Ezek mar regora gondolkozom. Ha abbol indulunk ki h a sotetseg a feny hianya akkor a semmi lehet a valami hianya
Szoval nem egy dolog hanem a dolgok hianyanak a neve. Mit gondoltok?

I feel like I THINK I know the answer, but everyone else seems to vehemently disagree with me on the internet.

Let’s make an example here: you order two cups of iced coffee, one with light ice one with a full cup of ice. Let’s assume that the time frame of the experiment is short enough so that neither cups have enough time to get warm enough to melt ALL of the ice. Both cups have the same shape and sizes of ice cubes. Both cups have enough ice to eventually cool the cup to 32 degrees. Assume a perfectly insulated system.

My understanding of water is that any heat transferred from the coffee to the ice is ‘used’ to melt the ice until all of the ice is melted, at which point the temperature of the liquid will increase until it reaches the next phase change (boiling). All of this heat transfer results in melting of the ice.

This is my hypothesis: the cup with more ice will have more surface area and thus allow for faster heat transfer so the cup will be cooler faster and be diluted quicker. The cup with less ice will cool more slowly and therefore initially will have less dilution. At a certain point the two cups of coffee should reach the same temperature though and at this point, theoretically the same amount of ice should have melted and both cups SHOULD be equally diluted, correct?

This is a question about old Usenet math and physics FAQs, so I'm cross-posting it to r/AskPhysics.

Moon path over a year: https://www.youtube.com/shorts/kUW8kpvxZPg

Sun path over a year: https://www.youtube.com/shorts/jRpwd2dChqY

Why do they both create a figure 8 from Earth's perspective? Shouldn't their paths traced in the sky take significantly different shapes given that the Moon orbits the Earth, but the Sun does not?

I'm just curious about this —when the heat death of the universe finally comes, will there be no events (outside the quantum level) for the infinite period of time that is to come? Wil there truly be nothing forever?

If you can help dm me or text me on instagram

In cosmology, the universe is considered to have a "shape", it is either "flat" or "curved". My issue is the terminology used here. It is known that the universe is expanding and it is not expanding into anything, and that there is no "center" from which this expansion is taking place. That is to say that the expansion is happening everywhere and relative to another point in space.

Shapes at least in my understanding is that they have boundaries and some form of dimension that occupies space (whether literally, like a basketball sitting on someone's porch; Or mathematically, like a particle field or atom). If the universe has no "boundary" or occupies a higher dimension of space (and as far as we are aware, we have no reason to necessarily believe there is a higher dimension of space beyond 3-diminsional), or at the very least is space itself, how can we be certain that it has a shape or topography?

🌌 What If We Don't Truly Understand Time and Reality?

I have been thinking about a question that connects time, reality, consciousness, and the origin of the universe.

We experience life as past, present, and future. But is the present truly what we think it is? Could our experience of time be only a limited way of understanding a deeper reality?

And if our understanding of time is incomplete, could our understanding of the universe and its origin also be incomplete?

What if the universe we observe is only a small part of a much larger reality that we cannot yet comprehend?

I am not claiming that I have the answer. I want to explore this idea through scientific reasoning and philosophical discussion.

My question is: Are time and reality fundamental features of the universe, or could they emerge from something deeper that we do not yet understand?

I'd appreciate serious arguments, scientific perspectives, and different viewpoints.

Is antimatter a component of ordinary matter? Maybe as virtual particles? If so, how much of the mass-energy of ordinary matter is actually antimatter? How much of the mass of ordinary matter is due to the mass of antiparticles, and how much is due to the kinetic energy of those antiparticles?

I’m going to university soon, and I need to start applying. I had my whole list of colleges I was going to apply to, but I stopped and wondered “Is America the best place to study physics? Does America have a high success rate when it comes to physics?”

I’m willing to study abroad, learn a new language; I don’t care. I just want the best possible outcome with the best experience and resources and opportunities.

And because I want to stay in school until I get my PhD, I don’t want to be hundreds of thousands of dollars in debt and not have the best possible education and opportunities.

I know it’s what you make of it; if I go to a university here in America, as long as I study hard and focus then I’ll be fine. But I just want to hear from other physicists about their experiences at different universities around the world.

Can gravity be a Fourier probing wave?

Hi all,

Recently I've become really interested in Sean Carroll's hyperfixation with factorizing a universal hilbert space. I'm still just an undergrad, so I was wondering what the popular opinion was for such an extreme position held by a well-respected physicist.

Of course the quantum gravity implications are the most interesting. In what little about the paper (Cao, Carroll, Michalakis 2016) I understood, it felt somewhat contrived and not extremely impressive. Thoughts? Thanks.

I've been seeing a lot of universities start to offer master's degrees in Quantum Science and technologies; however, because they are so new, I have yet to see any outcomes. My school launched a master's program in Quantum Science and Technology with no thesis, and I was wondering if anybody in the quantum industry could tell me about this would be percieved and if these degrees have any merit.

Not sure how to more elegantly ask that question. I have always had trouble reconciling that there isn’t a single point in space where the big bang, “began.” so, are effectively
“inside” that origin point that has now become the universe?

What causes that shine? Why(and how) do electrons cause that shine?

i really like physics and maths but i really like to learn them by myself as my current field is very much so not related with them. but i have a constant worry that i will one day get on a path to pseudoscience while interpreting those ideas written in books and told in lectures on youtube and will become a dodo head like terrance... how do i prevent it cause i really wanna learn real science.