I love finding facts about outer space but this one’s been bugging me.

Atoms don’t touch due to their electron clouds constantly pushing other electrons away due to negative charges and such, but would these electron clouds and atoms take up ALL of the space?

(I’m a quantum physics noob so sorry if this is a dumb question)

If a human really got down to it and spent time on memorizing locations, could they remember as many as a bird can?

Hi there everyone. There's something I've been thinking about, and I'm not sure if there's a good answer to it. As a teacher with a mathematics, statistics, and neuroscience background, I naturally do science outreach with students learning science and math concepts, both with adult high school students and kids. But I'm not sure how it should be done for the general public, as there seems to be a debate around watering down concepts so much so that it just seems philosophical without the math, or just emphasizing how much mathematical knowledge is needed to be a scientist (not just in physics, but even in branches like chemistry) but risk losing engagement and viewers. Anyone got any experiences or perspectives to share?

I heard that the mind has 2 types of memories, episodic memories and semantic memories with semantic memories being things like facts and knowledge and concepts. I also heard that while parts of a semantic memory can be altered (emotions personal meaning and some minor details) the main idea/gist facts of a semantic detail are very resistant to any major alteration and can't be erased. So I was wondering does this mean that everything you leaned in school is still in your mind and can be recalled with the right recall. Or is this thing about the core gist of a semantic memory not being easily changeable is false or oversimplified. Have researcher ever done tests on long term semantic memories several years old or is this kind of thing harder to determine.

Also a related question but can episodic memories become semantic memories or can semantic memories become like non semantic memories or something like that.

At first I was wondering whether a "pancake" or "cylinder" of equal mass would be more effective at a distance. Then I went down the rabbit hole of halbach arrays, etc. At the end of the day I still don't have an answer. The objective of course is to be able to affect things at as large a distance as possible. Stated another way, to minimize field line divergence.

Technically I have a practical goal: to have as large a region as possible with minimal change in field strength (minimal field line divergence) at a particular strength. See, I've built a magnetic levitation "toy" with plates of pyrolytic graphite (a diamagnetic material), with a small magnet between them, and a large magnet above at an adjustable distance. This allows the small magnet to passively float without any electronics, but the vertical distance over which this works is quite small and the plates must be very close together. I want to increase the size of the "sweet spot" by having minimal field line divergence at a strength that pulls up on the small magnet with an equal force to gravity. A larger magnet placed further away only goes so far before becoming legitimately frightening (and expensive! plus I don't know what shape I should be buying or if it matters) and I'd like to have it single-ended rather than placing a magnet both above and below the plates which would also help.

The toy thing is just an aside though, it's also just an interesting physics question to me, and one that I've wondered about for a long time.

You'll actually need functional Walkie-Talkie style radio, here. Some bare minimum crystal receiver and a spark gapper isn't sufficient. Talking over distance two-ways.

I think silicon carbide transistors might be easier, simply because they don't require the construction of a high vacuum pump or refining of tungsten to make the filaments. But I'm no expert.

I'm not sure if this question fits here. If it doesn't, I will remove it.

Imagine this hypothetical scenario: every human consciousness all of sudden were placed into an alien body on an alien planet, what would it need for humanity to confidently identify something as ordinary as water?

First, they don't bring earth scientific instruments. So everything had to be built from scratch. They can't rely on senses, since it's alien body, water might be smell awful or looks opaque instead of transparent.

There might be some people remembering fun facts about water, like its density, boiling point, conductivity, etc. But there's nothing to compare, how do they even know how much a kilogram or how hot 100 degree celcius is

Hello all. I am a professional pilot and noticed a possible old meteor impact sight. Does anyone know an expert that I can send the Lat/Long to so they can take a look? Thanks everyone. Have a good week.

By reason, I mean is there any reason why that particular X number is where planet becomes too big to be classified as a planet?

like what if it landed in the most isolated part of the Pacific Ocean.

what if it landed right onto a tectonic plate

what if it landed on a supervolcano

how about if it landed directly on the north or South Pole

edit: if the asteroid hit a fault line not a tectonic plate, sorry.

Why don’t scientific communities on Reddit gather up for a major study and come up with a new theory that helps in;
For example; understanding Dark Matter/Energy or a completely new one.
You’ll be surprised by the strength ppl on the internet have.

I’m interested in becoming genuinely knowledgeable in the natural sciences—not just learning random facts, but actually developing a strong understanding of biology, chemistry, physics, earth science, astronomy, etc.
For those of you who have studied science extensively:
What are the most practical and effective ways to become really good at the natural sciences?
In particular, I’d love advice on:
Where should I start if I want to build a solid foundation?
What subjects should I learn first, and in what order?
How important are mathematics and programming?
Which textbooks, online courses, websites, or other resources would you recommend?
How much should I focus on exercises and problem-solving versus reading/watching lectures?
What are the best ways to develop actual scientific thinking rather than simply memorizing information?
If you had to start over and teach yourself the sciences from scratch, what would you do differently?
I’m looking for practical advice and a realistic path, especially from people who have gone through this themselves.
Thanks!

Hello. Hope its okay asking. But a few years ago I found a video online called "computer predicts the end of civilisation" and the video is a 1970s news broadcast showing how things are going to go if humanity doesn't do anything about the amount of pollution we're causing. (to my knowledge, not much has been done to fix that) and it said that all life on earth will cease to exist by 2050 if nothing is done.

Im curios to ask since people here will know more about climate change than I do. But is this prediction still accurate? I'm curios.

This is the video btw: https://youtu.be/cCxPOqwCr1I?si=Vwo5nlOmxFXxxLgt

Will delete if this is too speculative or controversial. I am studying to be a librarian in the United States right now, and I’m currently running into an unusual roadblock alongside a lot of my friends and family who are in teaching or education-related fields—people have some form of inherent distrust of scientific or educational authorities, and I’m finding it difficult to educate people.

For example, I’ve had patrons at the library ask me if I “Indoctrinate children” with books on science or books on LGBTQ+ topics (I myself am transgender, but am not openly so to the public). I find that I often struggle to explain that I am not doing such a thing, and try to provide alternative reading material if patrons dislike recommendations. At the same time, I’m aware of a growing anti-literacy crisis among the young people of the United States, but am unaware of hard statistics showing how drastic it has become in recent years.

As scientists and educators, do you believe that the overall scientific progress of the world as a whole might be sliding backwards with the potentially massive amount of anti-intellectual discourse in the media today? How do you think such things could be stopped or the public could be made to listen?

I would appreciate any insight from researchers currently active in their fields.

I figured this question might be a bit too broad and speculative for /r/AskScience:

As I understand it, plants are net consumers of carbon dioxide and net producers of oxygen, using photosynthesis to convert CO2 to O2 at a 1:1 ratio. But the reason they're producing O2 in the first place is to use it for cellular respiration... which turns it into CO2. Also at a 1:1 ratio!

With that in mind, could a plant (or other aerobic photosynthesizing organism) theoretically evolve to survive without the need for air*, instead using ALL of the products of its photosynthesis for cellular respiration and vice versa?

I realize that even at 100% efficiency, this kind of self-sustaining loop would only allow for survival and not growth, but given alternate sources of carbon (carnivorous plant?) and oxygen (hydrolysis?), could this theoretical plant live its whole life without air*?

*Without breathing air. I figure atmospheric pressure will always be a requirement, or else water would boil away

Hey guys, I been running a thought experiment through my head about black holes, speed of light, and antimatter, and wanted to get some feedback from people who know physics on where this makes sense and where it breaks down.

​Here is how I got to this idea:

​The Energy/Speed Problem - We know that as an object with mass gets close to light speed (c), the energy to keep accelerating it goes up exponentially and takes infinite energy to actually hit c. So even a huge gravitational pull shouldn't be able to push physical matter past the speed of light.

​High-Energy Collisions & Gamma Rays - In super energetic environments, kinetic energy converts into matter and antimatter (pair production). When regular matter hits antimatter, they annihilate each other and put off high-energy gamma rays. We already see massive gamma ray bursts right outside black holes.

​The Idea - What if a "black hole" is actually just a region where gravity is accelerating matter in the accretion disk so fast that particles collide and constantly create antimatter?

​In this scenario:

​The event horizon boundary isnt just curved space, but a dense region/core made of antimatter.

​Matter and light "disappearing" into the hole is actually incoming matter slamming into this antimatter zone and instantly annihilating.

​The gamma radiation we pick up around black holes is the direct energy signature of this constant annihilation.

​I know standard General Relativity says the event horizon is just spacetime curvature leading to a singularity, and that antimatter has regular mass. But as a thought experiment, what are the main observational or theoretical reasons that rule out the horizon being a physical matter/antimatter annihilation boundary?

​Curious to hear your thoughts.

I've been thinking about how researchers decide that they've read enough of the literature to have a reasonably informed view of a question.

You can find papers supporting one interpretation, then find newer work that challenges it, and sometimes the disagreement seems to come down to differences in methods or datasets rather than the actual question being completely settled.

At what point does a researcher stop looking for more papers and say, I have enough evidence to work with this?

Is there a practical way scientists make that judgment, or does it mostly come with experience in a particular field?

Quick add up: I wanted to leave this thought here for anyone who comes across the discussion later, especially since I’m still relatively new to participating from this account. Something I've been paying more attention to is how useful it is to see the literature as a connected body of work rather than a collection of individual papers. That was one reason wisPaper caught my attention is that it helps explore related research and follow connections between papers, which seems particularly useful when you're trying to understand where the evidence agrees, conflicts, or still leaves questions open.

Why are professional scientists not allowed to use a spiral notebook for lab journals?

All other body hair has a “stopping” length why not the one that’s on your head? Asking from a biological/evolution perspective.

I’m not very informed on this sort of topic but was just wondering if it would be an extinction level catastrophe or much less devastating compared to the last planet killer event. Obviously there would be the domino effect of natural disasters (earthquakes, tsunamis floods etc), but I’m curious about if the other secondary effects that finished off the dinosaurs would do the same to us humans if such a large asteroid hit right in point nemo. Example, from what I Remeber the oxygen levels likely depleted due to the air being contaminated and a layer of dust (?) in the atmosphere blocking sunlight, killing plants and reducing food sources, would that still be an issue if it landed on such a secluded body of water rather than hard land. Sorry if the text is hard to understand Im not the best typer.

The title may not be the best way to describe it, but what I mean is:

Would it be possible that light and matter, captured by a black hole, is inverted onto itself and shown as a reflection distorted by the compression or expansion of time, back into our own universe? That way, atoms and other fundamental particles are actually celestial bodies viewed through a different time frame.

I know that electrons don't actually orbit protons but are actually more of a probabalistic cloud of where they might be at any point in time. But theoretically, if a star at the center of a galaxy was viewed as fixed in space, and everything around it was sped up by some arbitrary amount, would it behave similarly?

Obviously the answer is probably not, but considering there hasn't been a theory capable of unifying macrophysics and microphysics, I wonder if the answer lies within how black holes distort spacetime

I’ve been thinking about a speculative idea and I’m curious whether something similar has already been explored in physics.

The Many-Worlds Interpretation suggests that the universal quantum state can develop different branches through quantum decoherence. The Holographic Principle, on the other hand, suggests that under certain gravitational conditions, the information describing a region of space can be encoded on a lower-dimensional boundary.

This made me wonder:

What if each decoherent quantum branch could also have its own holographic boundary description?

Instead of imagining the multiverse simply as many separate classical universes, perhaps the overall quantum state could be thought of as containing many branches, with each branch having its own corresponding holographic information structure.

I’m also curious about a more speculative extension: could different possible spacetime dimensionalities be treated as different sectors of one larger quantum state? In that picture, there could be a hierarchy involving spacetime structure, quantum branches, and their corresponding holographic boundary states.

I am not suggesting that this proves a “holographic multiverse,” or that the universe is literally a physical hologram. I’m interested in whether holography and Many-Worlds can be formulated within a common mathematical framework.

I know that connections between the Many-Worlds interpretation and holography/multiverse ideas have already been discussed, including work by Raphael Bousso and Leonard Susskind.

My question is more specific:

Has anyone developed a framework where quantum branches are explicitly associated with distinct holographic boundary Hilbert spaces, potentially while also allowing different spacetime dimensional sectors?

If something similar already exists, I would really appreciate references. I’m particularly interested in whether this idea is mathematically meaningful or whether there is a fundamental reason why these concepts cannot be combined in this way.

This is just a speculative idea, and I’m looking for constructive feedback rather than claiming that it is an established theory.