When I was a graduate student, I studied magnetism in massive stars. Lower mass stars (like our sun) demonstrate convection in their outermost layers, which creates turbulent magnetic fields. About 1 in 10 higher mass stars (more than ~8x the mass of the sun) host magnetic fields that are strong and very stable. These stars do not have convection in their outer layers (and thus can’t generate magnetic fields in the same fashion as the sun), and it is thought that these fields are formed very early in the star’s life. Despite much effort, we haven’t really figured out how that happens.
I love how you stopped to explain stuff like what a big star is, but not the funny magnetism itself
If the solution to a problem is easy to check for correctness, must the problem be easy to solve?
For instance, it is easy to check if a filled sudoku grid is a valid solution. Must it therefore be easy to solve sudokus?
Most people would probably intuitively answer “no”, and most computer scientists agree, but this has still not been proven, so we actually don’t know.
That’s actually the simplest and clearest description of the P/NP problem I’ve ever read.
Well, there’s counterfactual examples of this, so it must not be true.
In pretty much every single relationship worldwide, one person can very easily determine if the recommendation from the other for where to eat or what to watch is correct or not.
And yet successfully figuring out where to eat or what to watch is nigh impossible.
I think there’s a
fighterfurther* problem, it may be true and we just don’t know the easy way to do it.
I think my favorite troll statement to a mathematician/comp scientist is:
“Actually, P > NP - there exist problems where it’s harder to verify a solution than to arrive at one”
Most people would probably intuitively answer “no”, and most computer scientists agree, but this has still not been proven, so we actually don’t know.
I disagree, I think most computer scientists believe that P != NP, at least when it comes to classical computers. If we believed that P = NP, then why would we bother with encryption?
EDIT: nvm, I misread it.
I think you’ve misunderstood 😅. Answering “no” to that question corresponds to P != NP (there are problems that are easy to verify but not easy to solve), while “yes” means P = NP (if a solution is easy to check, the problem must be easy to solve). So I am saying most people and most scientists believe P != NP exactly as you say.
Reading comprehension is hard my bad.
Edit: wait no, it’s “easy” I’m just dumb.
Isn’t it proof enough? Using the Sudoku example: there are certainly different levels of difficulties, depending on how many numbers are set in the beginning and other parameters. Checking if the solved answer is correct, is always the same “difficulty” - thus there is no correlation between the difficulty of the puzzle at the beginning and checking the Correctness. Some people might not be able to solve it, but they certainly can check if the solution is right
Isn’t it proof enough?
Unfortunately no. The question is a simplification of the P versus NP problem.
The problem lies in having to prove that no method exists that is easy. How do you prove that no matter what method you use to solve the sudoku, it can never be done easily? You’ll need to somehow prove that no such method exists, but that is rather hard. In principle, it could be that there is some undiscovered easy way to solve sudokus that we don’t know about yet.
I’m using sudokus as an example here, but it could be a generic problem. There’s also a certain formalism about what “easy” means but I won’t get into it further, it is a rather complicated area.
Interestingly, it involves formal languages a lot, which is funny as you wouldn’t think computer science and linguistics have a lot in common, but they do in a lot of ways actually.
You can solve any sudoku easily by trying every possible combination and seeing if they are correct. It’ll take a long time, but it’s fairly easy.
What if the sudoku is 1 milllion lines by 1 million lines? How about a trillion by a trillion? The answer is still easy to check, but it takes exponentially longer to solve the board as the board gets larger. That’s the jist of the problem: Is there a universal solution to a problem like this that can solve any size sudoku before the heat death of the universe?
Well it just so happens that the definition of “easy” in the actual problem is essentially “fast”. So under that definition, checking every single possible solution is not an “easy” method.
For the purposes of OPs problem (P v NP), it considers not particular solutions, but general algorithmic approaches. Thus, we consider things as either Hard (exponential time, by size of input), or Easy (only polynomial time, by size of input).
A number of important problems fall into this general class of Hard problems: Sudoku, Traveling Salesman, Bin Packing, etc. These all have initial setups where solving them takes exponential time.
On the other hand, as an example of an easy problem, consider sorting a list of numbers. It’s really easy to determine if a lost is sorted, and it’s always relatively fast/easy to sort the list, no matter what setup it had initially.
Trying to prevent bacteria from developing antimicrobial resistance. At these rates in 30 years antimicrobial resistant bacteria are projected to kill more people than cancer.
We really need a big push into bacteriophage research I think. Get the bugs all killing each other so we can keep our antibiotics for emergencies.
Clearly you need to figure out how to give antibiotic resistant bacteria cancer.
That sounds like a quick way to make super tumors
Uncontrolled dividing of the most dangerous bacterias known to man? What could go wrong?
Lol!!! Yes!!!
I’ve been around the AMR space for a while, but only as a collaborator. Have helped do some bacterial assemblies and help find methods of detecting ICE. I’m a bioinformatician so I get to jump onto a bunch of different projects.
AMR is scary and not really in the public knowledge of upcoming issues. I think about it every time my son had an infection while he was very young and hope he didn’t get a resistant strain.
So are there any good news in this respect?
There was a paper back in December about a new class of antibiotics being discovered thanks to the use of Deep Learning.
This looks like a decent writeup about it, the paper itself is not open access
This is very welcome as it has been a long time since the last new class of antibiotics was discovered. Here’s a good paper that talks about the timeline of antibiotics
It’s been a little while since I took the AMR course, so I’ll let the papers speak for themselves instead of trying to quiz myself here on Lemmy.
How much of this resistance is down to feeding livestock antibiotics compared to doctors over-prescribing to people, or what is the cause do you know? Is there any way to slow down the rate?
The level of AB use in livestock in various countries is astonishing.
Most european nations have to keep a very strict log of which antibiotics are used, and for what reason.
Meanwhile, until recently India was using Colistin as a growth promoter.Given the search summary of that one is “an antibiotic medication used as a last-resort treatment for multidrug-resistant Gram-negative infections”, that sounds very bad.
I saw numbers on this recently. It was something like 80-90% of all antibiotics are given to livestock. So this is a huge contributor.
I think there are so many new and great ideas in this space but you have to consider how science is funded. Funding bodies and reviewers want incremental research that is safe. This has led to our current situation. Phage therapy has been around for so long but is only in the last 10 years gained creditability and treated as a path to take. Ultimately, antimicrobial resistance is incredibly solvable even at a policy level and definitely across many scientific levels. But it requires more cooperation than farms, pharmacies, hospitals, states and countries can muster.
I’m only a professional scientist in the loosest sense of the term but for years we’ve tried to figure out why Joe can’t leave the break room to fart and who the fuck does he think he is?
He’s the president!
I’m in the building sciences. The biggest unanswered question we come up against almost daily is “what the fuck was the last guy thinking?”. And we avoid, daily, admitting we were the last guy somewhere else.
How many sciences have you built?
Former intoxicology tech, was both guys daily lol.
This sounds like software engineering in a nutshell.
Software engineering is the study of constantly calling your predecessor an idiot.
Especially when you are that predecessor
We still don’t understand quite how the brain works or how consciousness comes from neurons.
Super interesting! I watched an explainer last night about a theory that consciousness arises from space-time collapse quantum wave functions in microtubules.
The vast majority went straight over my head but the host stated that the theory was seen as completely insane by their peers and just recently it’s gaining credibility because of some new research in the past few weeks.
Any thoughts on this?
https://en.m.wikipedia.org/wiki/Orchestrated_objective_reduction
Is this theory what you’re referring to? Just curious because it always seemed interesting to me but I’m not educated enough to even know how to approach the subject beyond going, “huh neat.”
Ahh jeez the Penrose theory. This theory gets less neat the more you learn about it.
Sounds like they really don’t want their lives to be deterministic. I’m skeptical of anyone who jumps to quantum mechanics to explain consciousness. Would love to know what research you are referencing.
Thanks! Very interesting. Looks like we have some quantum activity going on after all. Though, there is a large chasm between observing activity and proving its necessity for our consciousness.
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Origin of life matters to a lot of people I think. RNA vs other self-replicating molecules? Moon-based tidal PCR? Cell formation etc.
Is P, NP?
Guys I swear this actually makes sense…
I solved this in undergrad.
P = NP when N=1. I don’t understand what the big deal is.
Also P is 0 when N is 0
I don’t think you passed
How to accurately estimate signal crosstalk and power delivery performance without FEM/MoM simulators.
For people and companies that can’t afford 25k-300k per year in licence and compute costs, there is yet to be a good standard way to estimate EM performance. Not to mention dedicated simulation machines needed.
That’s why these companies can charge so damn much. The systems are so complex that making a ton of assumptions to pump out some things by hand or with bulk circuit simulators often doesn’t even get close to real world performance.
If someone figured out an accurate method without those simulations, the industry could also save a shit ton of compute power and time.
As someone on the outskirts of Data Science, probably something along the lines of “Just what the fuck does my customer actually need?”
You can’t throw buzzwords and a poorly labeled spreadsheet at me and expect me to go deep diving into a trashheap of data to magically pull a reasonable answer. “Average” has no meaning if you don’t give me anything to average over. I can’t tell you what nobody has ever recorded anywhere, because we don’t have any telepathic interfaces (and probably would get in trouble with the worker’s council if we tried to get one).
I’m sure there are many interesting questions to be debated in this field, but on the practical side, humans remain the greatest mystery.
Probably not the most complex, but in programming, the salesman problem: intuitive for humans, really tough for programming. It highlights how sophisticated our brains are with certain tasks, and what we take for granted.
Also, related xkcd.
I once accidentally worked myself into trying to solve the traveling salesman problem. I was doing some work on a very specific problem, and I got to a point where I couldn’t figure out a way to efficiently link up a bunch of points. The funny thing is that I knew about the TSP, but I just didn’t realize that the problem I was trying to solve was a case of the TSP. After a couple of days trying to figure it out, I realized what it was, and that it was futile.
It was a good lesson to always try to find the most abstracted version of the problem you are trying to solve cause someone smarter has either tried and failed or tried and succeeded.
Predictability in a chaotic system across various scales of time and space.
How does immunology work?
Pro tip: nobody understands immunology and anyone who tells you otherwise is lying
My field of expertise is bacterial pathogenesis with a particular interest in pneumococcal pneumonia.
And it’s true, immunology is ridiculously complex that no one person can ever hope to fully understand it. Immune cells are helpful or detrimental depending on the context, and sometimes even both. And we don’t really fully know why. The problem is that pathogens and humans have been in an evolutionary arms race for billions of years, and unraveling all of that evolutionary technical debt is Fun™
To give an example, Toll-like receptors are one of the most important pathogen-detection mechanisms, and they were discovered just about 25 years ago and people only really figured out their importance about 20 years ago. There are researchers who have spent the majority of their careers before the discovery of one of the most crucial immune pathways.
We really don’t know what’s going on with immunology and to say otherwise is, as I’ve said, an outright lie. People seem to overestimate how much we know about the immune system, not knowing that we are still very much in the “baby phase” of immune research. The fact that we are able to do so much already is really kind of a testament to human ingenuity than anything
My personal experience is that people who claim to know completely about how the immune system works is more likely to be a science denier (or more likely, naive)
