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==COSMOLOGY==> ‘Uhhh … how sure are we that everything is made of these?’
Somewhat related, back in highschool I was really enjoying chemistry class. Super fun stuff, definitely a career path. Then when we were doing the math practices, I got a question wrong that I knew I combined correctly.
I asked the teacher and she said “oh yeah that one just doesn’t follow the rules” instantly killed my enjoyment of chemistry.
Aw that’s too bad. That response I’m sure you’re paraphrasing, but “that one doesn’t follow the rules” is the best part of science.
It means our rules aren’t good enough, or we don’t understand that one well enough. Figuring it out can be an entire career of discovery. And the reasons why can be fascinating and inspiring to more discoveries!
In this case, it was probably the teacher not being knowledgeable enough to explain a more advance theory that goes beyond the simple model he was teaching. What’s sad is that the teacher didn’t take the opportunity to dig deeper with the student, it could have been very motivating for the student to feel like he found something that went beyond the normal curriculum.
Might be idea gas law.
High school chemistry felt less like imperfect modeling and more like alchemy that sometimes yields tangible results. I can’t remember specifics anymore but there were many moments where I was like “you’re using too many shortcuts and this doesn’t make any damn sense mathematically or dimensionally anymore”. I know real chemistry is too complex to fit a high school program, but the way it was taught really was like a soft science cosplaying as a hard science.
Also chemists would use any pressure units before they used Pa. mmHg as a unit suffers from congenital defects I can only assume stem from repeated inbreeding.
or it’s ochem
At school, I thought our understanding of chemistry was really good. Years later, I realized that complicated solutions aren’t covered by any of the equations we have. You’re can do fancy calculations, but you’re always stuck with simple solutions and standard conditions. In real life, you have to deal with super messy non-standard stuff all the time.
Top scientists end up developing semi-empirical models, or even particle simulations, and that’s the best we can do right now. Nobody fully trusts those predictions, so we’re still going to need lab experiments before making any big decisions.
The good news is that there’s still so much to discover.
It’s similar to what I felt learning organic chemistry. That’s why I ended pursuing a career in math.
You aren’t following the rules! You’re supposed to nonchalantly get the correct answer and thus discover a new rule that we nowadays know as the Galapagon Principle.
One of my great regrets in high school chemistry was that I was born too late to discover some pattern and have it called Liz 's Formula or whatever.
I never seriously studied physics. A few years back I decided that it was time to push myself a little and start reading up. I started with some articles on string theory and suddenly remembered why I didn’t want to study physics.
Looks like I saved twice as much time as I thought I had.
I started with some articles on string theory
Yeah, that’s a mistake.
Unless you understand the working theories out there, you gain nothing by going deep into speculative ideas.
You could try reading Feynman’s lectures, he was a very passionate teacher, and he used intuition a lot, so you don’t need to grind on equations to follow. https://en.wikipedia.org/wiki/The_Feynman_Lectures_on_Physics
Thanks.
You can read them for free
Thanks a second time!
String theory is barely a scientific theory, it’s an untestable (experimentally) mathematical framework.
I’m far from an expert on this, but I don’t think this is the best introduction to physics.
If strings are just a theory then how do you explain shoelaces? 😏
There are many kinds of ‘string.’
For example, you just made a second string joke.
What are you gonna do, string me up for it?
We really should have more stringent requirements for joke quality here.
We would do that of you didn‘t keep stringing me along!
According to the article it’s no longer a credible theory
It’s not untestable. It gives predictions and there has been tests for those predictions. The unfortunate part is that the predictions are often not very concrete, and the range of a lot of these predictions lies far beyond our capabilities. But people are looking to measure them indirectly in various ways. So it’s not like it is untestable by design or anything like that.
AFAIK, every single idea from string theory that could be tested was rejected. And the theory was made more complex, less predictive so that it could still work without the testable idea.
These are very broad statements that are not very easy to comment on. “Every single idea”, makes it sound like they are a lot, I would not say they are. “Was rejected”, depends what you mean… " did not show positiv results", “no longer possible to motivate economically”, sure, " refuted as bullshit", not so much. “Was made more complex”, sounds like there is intent, and/or, depending on what you mean by complex, that it would be necessarily a bad thing to using more advanced maths to formulate things you could not before, and hence solve new problems.
I can mention two possible avenues of inquiry that are less than 5 years old that has sprung from string theory as possible support for it: signals of black hole structure in gravitational wave ‘ring downs’ of black hole mergers, and the exclusion of a positive cosmological constant. But if you know that these are untestable or rejected, I’d love to hear about it.
I thought the problem with string theory is that its predictions match up with what the standard model already explains. Maybe that’s only for the things we have the capability to mature any time soon.
No, the problem is very different. In string theory you have a lot of freedom to build various models, and they can provide the standard model, slight deviations from it, or something completely different. Before LHC we knew we had some version of the standard model, the hope was that the LHC would find that we have some particular deviation, like supersymmetry (susy) with such-and-such masses and particles. It did not. The prediction is susy, the problem is that the prediction (at least yet) is not exactly this type of susy. String theory says there is supposed to be a lot of extra stuff beyond the standard model, question is just how do you find it, which is made harder by string theory allowing for so many models.
I did a semester of physics in high school and loved it. One of the few classes I actually enjoyed. I joined the nuclear program in the Navy and still loved it. I got to college and brought along all my ACE credits so I got to skip some math, physics, early chemistry, and thermodynamics.
We got to experimental physics and it broke my brain. I barely walked away with my BS and even though I could have made good money I never ended up using the degree because I ended up hating the whole field. It hangs on the wall next to my certificate from a two week bartending school.
I ended up with a long and fruitful IT career where I’ve never had to apply even a little knowledge I gained from that degree.
Thanks for the story.
Nice to know I’m not the only one.
Half-expected to see a wumbo boson in that article as a reason for “that” SpongeBob episode
What is this author for XKCD’s background? He seems to know a lot about a lot of complex subjects. I’m always impressed.
Degree in physics. Worked for NASA as a programmer and roboticist. Full time “cartoonist” since 2006.
Sounds like he’s related to this guy
At my work, we meet astronauts fairly often (I met Jonny Kim last year), and it’s amazing how many of them are like this. They’ll usually pass out their headshots that have their bio on the back, and the number of advanced degrees and impressive accomplishments is jaw dropping. Like I feel like I’d think my life was worthwhile if I did one of those things by the end of it, and a lot of the astronauts are hardly more than half my age. And to really rub it in, they all seem incredibly genuine, personable, and well adjusted.
There are a giant number of people who want to be astronauts, and NASA only needs a small number in a given year, so they can pick the very cream of the crop.
At least we’re sending space our best.
Could you imagine what the world would be like if we let their like lead our countries?
Ah, a meritocracy instead of a plutocracy. Maybe someday, if we survive.
When you rule, you get to pick what qualities have merit, which is how we end up of administrations of The Master Race or lispy Spaniards, or ruthlesd billionaires.
We’re still trying to figure out how to get to government tha implements public-serving ideas.
Just wait until you learn about Johnny Sins
It’s understandable that he didn’t have time to learn how to draw, then.
Per the alt text: How do we know that particles are the smallest bits? Let’s zoom in even further.
These are the questions that make me feel such an insane sense of wonder and awe.
How deep does it go?
How high does it go the other way? How big does existence get?
Why is there something rather than nothing?
What is nothing made of?
Nothing is more of a definition than a thing. It’s just the absence of matter.
Even in the absence of matter, there’s still the quantum foam. The most perfect vacuum is teeming with this energy. To truly understand the nature of ‘nothing,’ one would need to venture beyond spacetime itself—and even then, it’s not guaranteed that ‘nothing’ would be found. Physics suggests that anything existing outside of or predating spacetime would generally have no impact on us; it doesn’t necessarily explain what the ‘outside’ might be like.
I’d say nothing is less a definition but rather an informal shorthand for how we percieve at macro scale with our wrinkly 4D brains.
And then even when you try to peer behind the definition of “nothing” with math all you are greeted with is infinities which we handily just swept under the rug and pretended to be zero so we could define a “nothing” state in the first place!
Right, it’s part of what leaves me in such awe. What lies beyond? It seems nonsensical to us because we are defined by the gameboard we play on. The concept of the table it’s sitting on makes no sense. How could we ever hope to detect or understand something like that, something that exists beyond our space time, with no ability to build instruments in anything above 3 dimensions plus time.
That’s not really considering existence that deeply though. Nothing has to be something. Gravity and radiation are transmitted through the void of particle-less space. If nothing were truly nothing in an absolute sense…that couldn’t be possible. Something permits information to pass from point to point through interstellar space where there are on average 100 particles per cubic meter.
What did the universe explode into during the big bang and expansion?? Nothing is actually really weird.
I recommend all of the videos on history of the universe on YouTube
It’s turtles all the way down
What is nothing made of?
Oooh! I know this one! It’s Quantum Foam! 😁
Cosmology you put enough mass in a small enough area it becomes a singularity.
Quantum mechanics information can’t be destroyed to an unrecoverable state so singularities are impossible.
A big bang could recover it, you don’t know. It’s statistically possible and that’s all that counts
Crazy thing is very similar mathematical structures is used to define the behavior of a single particle in QFT and of a huge collection of particles in condensed matter physics
It’s not crazy when you think they are both trying to model the same universe.
When you section off a small part of the universe and try to model it, there’s little reason your model should look like a model for a completely different small part of the universe. Not unless they share fundamental characteristics that you’re trying to model. The math that describes permanent deformation looks nothing like fluid dynamics.
Recursive universe theory strikes again.
Recursive universe theory strikes again
They are both describing the same particles.
I mean in the case of the comic, yeah the reason for the behavior actually is tied to pretty much the same principles, but the generalized statement you made isn’t, well, generalizable.
They are both describing the same particles.
Water and ice are made up the same particles and molecules yet the mathematical structure to define the effect of force/pressure is very different - plastic deformation vs fluid dynamics as the example given above
Neither of them is trying to model the universe (that is the purview of cosmology). We are trying to model very particular phenomenon happening in the universe and there is no reason to expect them to modeled using the mathematical structure. The fact that they are is very fascinating.
Quantum field theory really aligns with my fap roulette kink.