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/sci/ - Science & Math

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Reminder: /sci/ is for discussing topics pertaining to science and mathematics, not for helping you with your homework or helping you figure out your career path.

If you want help with your homework, go to /wsr/ - Worksafe Requests.

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/med/ - Medicine General:

SPHIDER edition

Thread for the discussion of allopathic evidence-based medicine. We discuss research, offer advice (the best one is to see your family physician), make fun of premeds and shitpost.
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>>11543528
respond to my post
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>>11547167
Just because a butcher, this way you can cut meat without actually harming anyone with your mental retardation.
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>>11547171
Hehe just because a butcher
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>>11547176
Yeah I'm phonefagging, obviously I meant become*. Still better than the third world retard who can't use punctuation and can't tell 'then' from 'than'.
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>>11547171
“JuSt bEcAUse A bUtChEr”

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I've been thinking about the quantum resurrection theory, i.e. when you die, infinite years will pass until a string of events brings you back to life. And I thought: Time was infinite before I was born too, which must mean that my consciousness existed before I was born too, but I cannot remember it because all the memories were stored in my previous brain. Does that mean that consciousness alone is worthless without a brain host to perceive the world and store information in?
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>>11544377
It means that when you are reborn in infinite years you will still be a faggot
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>>11544377
OPs philosophical soul is awaking.
shhhh....
don't tell him about Open Individualism, Idealism and the hard problem of consciousness, will he discover it himself?

Will he follow the path of Einstein, Schrodinger and Schopenhauer or not?
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>>11546872
I want to point out open individualism is totally compatible with robo-fascist politics.
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>>11544377

All you can say for certain is that at any particular moment you are conscious of a certain number of things that are in your direct awareness. This includes perceptions as well as any memories and ideas.

What happened before or what will happen after this unit of awareness in the present moment, you have no way of telling for certain. You don’t even know if there is such a thing as a linear “history” in terms of a timeline in the physical world that your consciousness travels through.

It’s a mindfuck. We could be living in a multiverse where each mind experiences it’s own version of reality and all kinds of weird things can happen.
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>>11545568
>he doesn’t know about Big North

Poopy nigger butthole semen guacamole frisbee.

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All hail the Fourier Transform edition.

[eqn]\mathcal{F}\{ x(t) \} (\omega) = \int \limits_{-\infty}^{\infty} x(t) e^{-j \omega t}dt[/eqn]

What are you working on now that you have free quarantine time, anon?
Im doing DFT implementations on matlab
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I've read that a JFETs near their cutoff points are "square law devices". Does this literally mean I can use their amplification to solve the equation output=input^2 in analog? I'm asking because I've looked at how analog computers square numbers and its always sequence of op-amp logarithmic and antilogarithmic amplifiers. Why would people do that if they can get the same behavior from just a JFET and resistor?
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>>11546654
Are you being serious right now?
This is some basic shit from rudin chapter 3.
Please fuck off with your completely missplaced superiority complex, a lot of EEs delve seriosly into pure math topics, for example myself, im a math/ee double major.
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>>11546654
we do this proof in first year...
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>>11533683
>>11540280
>>11536368
Thanks I feel less bad about failing Signals Processing 2 times and passing it the third time around
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>>11546955
You majored in retardness, anon, sorry.

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What are the chances he survives covid-19?
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>>11547097
Based retarded reactionary
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>>11547097
not him but if you unironically think it's just the left then you're delusional and I suggest you go back to /pol/
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>>11547110
>go back to your echo chamber
that's exactly the opposite of what he needs tho
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I hope he doesn't, but obviously he will.
He really ruined things for me with that brexit thing. This is just how i feel truly. I wouldn't say it out loud in public. He doesn't deserve to die obviously but i would be slightly happier for a moment if he did. The more weak you are the more schahenfroude.

Am I a bad person ?
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>>11539195
>human race

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If we have genes for the cobalamine synthase, (actually several of them) does it mean we can synthesize our own B12, as long as there is some free cobalt in our food?
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We alreadt do, but in a stage where it's too late for our body to absorb it. It's in our feces.
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>>11546986
It can't be absorbed, retard.
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>>11547160
What can't be absorbed? Cobalt?

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and they kept telling me I have strong foundations with algorithms and data structures.
Any propedeutical book?
Coffee is not good for you.
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>>11544983
My intro ECE classes use
"Introduction to Computing Systems: From Bits and Gates to C and Beyond 2nd Edition"
It starts by teaching lc3 which is assembly language for a theoretical computer that is easy to learn.
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>>11546978
> for algorithms and data structures it's mostly basic algebra, complexity theory, and graph theory.
depends on the algorithms you're studying. Going deep and deeper into relevant combinatorial theory provokes proof mathematics, and that's definitely not something you can casually pick up without effort. Either way, you need the above listed to do something trivial or to get to a whiteboard interview, but it doesn't really get you the full breadth of the subjects. If your goal is to do nothing but the *basics* then sure, but if you want to program / work on nontrivial problems, then it doesn't suffice
>complexity theory
>not involving analysis for asymptotics
>not involving combinatorics, advanced graph theory, optimization theory, logic, abstract algebra, probability theory, etc.
wow, it's like you have little idea what you're talking about!
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>>11546133
I agree with this guy, unless you want to do OS programming or drivers or so.
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>>11546974
>well I have been told that, to become a good programmer, I need good foundations with Algorithms and Data structures.
True, but learning "Algorithms and Data structures" for the sake of it, in my honest opinion, doesn't serve much purpose. You get to understand various aspects of it (which is necessary, of course), but it doesn't map to real-world applications that well.

I'd suggest learning some simple high-level language like Python in parallel with C, just to get a feeling for what those "data structures" actually represent. Python has a lot of built in data-structures that are fairly well-accepted in general software engineering practice ("lists" aka arrays, "tuples" aka immutable arrays, "dicts" aka maps and so on). Doing C on the side will allow you to gain greater perspective on why are those "simple" constructs so powerful and expressive, and will give you a framework for when you actually start writing C code, so you don't (badly) reinvent everything from scratch.

Of course, reinventing everything is necessary for true understanding, but reinventing from SCRATCH, without watching all the current progress, is just an exercise in futility. People have spend decades researching those exact topics, and learning those might save you an enormous amount of otherwise wasteful effort.

TL;DR
While learning C, get a taste of other languages:

>Python
for general useful ideas about easy-to-use useful data structures

>javascript
just to get a feeling on why event loops are useful and how they work in practice

>C++
to give you perspective on how powerful metaprogramming (aka compile-time code generation by an algorithm) can be

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>>11544983
>and they kept telling me I have strong foundations with algorithms and data structures.
They are right.
>Any propedeutical book?
Knuth's series if you have the time.
>Coffee is not good for you.
It is in moderation.
sa >>>/g/ ed because off-topic.

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1.07068735 cm is the wavelength of 5G spectrum which is enough to affect small insects, birds, bees and god knows what other organs/tissues inside us.
Maybe not for a few months, but over the years it will cause some kind of damage that we will only understand after 70 years. Why are we not stopping 5G? Internet doesn't need to be this fast at the risk it poses to us and our environment.
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Current mobile broadband signals are proven to have negative effects over time as well, in humans and other animals (e.g. bees). If anything, we're already fucked and 5G won't make much of aa difference.

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Show me where the number 1 is in this image and I will concede.
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>>11547111

when will this meme end
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>>11547115
never, because it shows that there is a big problem within math. You can't just go on to say something less than 1 is 1
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>>11547111
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>>11547111
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>>11547139
It's not less than 1 though.

(I) If a central bank decided to issue a currency that is backed with a substance/element/compound/material/asset/object/art that is rarer and/or more expensive than gold, what will be the consequences of this policy?

(II) If a bank decided to offer smart contracts (derivatives certificates) that are equivalent to a set percentage of the value of rare substances/elements/compounds/materials/assets/objects/arts in exchange for cash or other payment (tangible or intangible assets). Also the derivatives certificates could be redeemed as cash if the things mentioned above are sold or the derivatives could be exchanged for type C shares of that particular bank. What would be the consequences of such policy?

https://youtu.be/VBGYQ51my5c

https://youtu.be/KGQTkWJ5mU4

https://youtu.be/h66rScoVEhI

https://youtu.be/-4iFy6AvJnw

https://youtu.be/j8qwb6IHrZk
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Currency right now based on made up feelings, it hasn't been based on gold for years. Currency based on made up feelings is the optimal currency for banks and governments to manage the economy.
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>>11545279
>(I) If a central bank decided to issue a currency that is backed with a substance/element/compound/material/asset/object/art that is rarer and/or more expensive than gold, what will be the consequences of this policy?
It would work in a similar fashion as the gold standard, restraining inflation but at the expense of surrendering an active monetary policy. This would result in an economy more prone to boom and bust cycles, with stronger economic growth during the boom periods, but more frequent recessions and panics as well. The role of keynesian or neokeynesian monetary policy is to "flatten" the boom and bust cycle in order to prevent recessions and provide more stable growth. See pic.

In the short term, it doesn't really matter which commodity you fix the currency to, as long as this commodity retains its value over time. The rate at which you fix the currency is more important than the currency itself. For instance, gold is more valuable than table salt, but if you fixed the USD to a rate of $2000 USD per gold ounce (when the actual price of gold is$1,669.25 per ounce) it would result in an undervalued currency, leading to stronger economic growth, more exports, but also more inflation. Likewise, if you fixed the USD to $70 per metric tonne of table salt (when its actual price is$90 per metric tonne) it would result in an overvalued dollar, with more imports, less economic growth, and very little inflation or even deflation.

In the long term, the commodity you are using is more relevant, because you would need the world supply of this commodity to grow at a steady rate in order to allow steady monetary expansion according to the needs of the economy. A commodity with a stagnant or falling supply would choke monetary expansion and result in massive deflation, constraining economic growth.
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>>11545476
>>11545279
>(II) If a bank decided to offer smart contracts (derivatives certificates) that are equivalent to a set percentage of the value of rare substances/elements/compounds/materials/assets/objects/arts in exchange for cash or other payment (tangible or intangible assets). Also the derivatives certificates could be redeemed as cash if the things mentioned above are sold or the derivatives could be exchanged for type C shares of that particular bank. What would be the consequences of such policy?
This sounds similar to the Rentenmark introduced in 1923 in Weimar Germany to stem hyperinflation, in practice it would also serve a similar role as the gold standard. These derivates, in effect, would act as a form of commodity-backed currency.
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Bump
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>>11545279
1. They would never do any backed currencies again. If gold is king, fiat is god.
2. It doesn't matter what they choose to back the currency with, it's the supply of the material backing it that matters. If the currency is backed by a commodity with a very volatile supply then the value of the currency will be volatile as well.
3. What would happen would largely depend on the policies enacted surrounding the banks' handling of the backed currency. If the laws don't change, the banks will do as they've always done and print more money regardless of how much gold is in their vaults.

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if h is = the planck length what would change
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https://youtu.be/3vNlf2zGLaE
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>>11547014
Spacetime is not some grid of Planck lengths and Planck times. The Planck length is ultimately a unit based on setting certain fundamental constants to 1. Because these include the gravitational constant and Planck's constant, the Planck length also serves as the rough order of magnitude scale of quantum gravity fluctuations. However, these fluctuations are still built on an underlying continuous background. A few particular speculative theories like Loop Quantum Gravity do propose quantized space and time on these scales, but again this is quite different from a discrete grid, and is not a part of consensus quantum physics.
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>>11547038
semantics. the plack length is the smallest length
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>>11547054
Retard
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>>11546966
Don't take the term quantization too literally, QM still treats reality as continuous.

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Farewell Dragon

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>>11546143
Very well
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>>11545513
the year has been a massive disaster since day 1, there have been very few good things that have happened this year
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>>11547136
The plague is a good thing. People need periodic mass adversity.
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>>11545513
Don't worry the government will fund spaceflight as usual even if the private sector is kill from the recession.
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>1 minute

What it is like to have a high iq?
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148 IQ reporting in. It's basically the same as living with an average IQ, the only difference being that you tend to have a harder time taking things at face value and you question what people say a lot more often.
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>>11543392
Beats me, anon. I take online IQ tests to feel good about myself, but when I'm around genuinely intelligent people, I feel like a moron.
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>>11543437
>https://test.mensa.no/
I got 133 too, that weird rectangle problem? Stumped me for like the last 8 minutes
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>>11546679
I was lost on the last three, ended up looking up the answers after the test. I never would have solved them on my own, at least not with the time constraint.
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Took it 3 times

1.) Assumed easy guesses simplest possible answer (overlooked better patterns) - 131
2.) Assumed hard pattern guesses and wasted time on easy problems looking for hidden patterns - 128
3.) Realized the way the problems work - 142

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Before the 19th cent. non-euclidean geometry was never really considered. Then hyperbolic geometry led to entire new branches of math and a deeper understanding of math.

What if we started doing math under a different axiomatic system? Like what if it wasnt assumed every natural number has a successor? Or if we didnt assume 0 is a natural?

Would this lead to new ideas in math?
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>>11545518
Sounds like model theory
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>>11547040
>Have some humility.
No u
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>>11547093
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>>11546648
Yes it is, it's a mapping from relation symbols to subsets of appropriately-sized tuples
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>>11547112
It's easy to be humble in the company of humble people. The real humility is keeping your cool when retards like me aren't. You're no better at me, so just accept we're both the same shit, and I'm just less educated than you.

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