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Griffiths vs Thomson?
>>
>>13109501
Thomson
Great book
>>
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>>13109509
Griffiths.
I'll fight you.

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Is there something more imaginary than complex numbers? i.e we say that √-1 doesn't exist but cool stuff happens if it does, what about things like 1/0, going past infinity, a statement that is neither true nor false etc?
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>>
>>13109075
One thing you need to understand about mathematics is that it needs to be consistent to work. Any new axiom or definition that leads to contradictions instantly breaks math. Truth and falsehood lose their meaning and doing any kind of reasoning becomes impossible. Introducing square root of negative one leads to a consistent theory, so we can do it. Giving a definite value to 1/0 would lead to contradictions, so we can't do it.
>>
>>13109573
>Introducing square root of negative one leads to a consistent theory
*consistent theory where the usual rules of arithmetics hold (well, most of them)
>Giving a definite value to 1/0 would lead to contradictions
*giving a definite value to 1/0 and assuming that usual rules of arithmetics hold
>>
>>13109389
But that means the =\= isnt true
>>
>>13109632
It is true for x if x=/= x.
>>
>>13109806
But x =\= x isnt true in this case. Are you mentally ill or smthing?

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From everything I've seen, the laws of thermodynamics haven't actually been proven. We know that for macroscopic systems they should be essentially true due to simple probability. However, I haven't seen any proof that an atomic-scale device couldn't reverse entropy. While it's very unlikely that a random youtuber can create energy using magnets, it isn't inconceivable that a complex organic molecule or a small nanobot could reverse entropy. Hell, the proof that Maxwell's Demon is impossible relies on the assumption that the laws of thermodynamics hold anyway.
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>>13085960
didnt read, just dropping in to say I want to have sweaty sex with Kurisu. Bye
>>
>>13085960
Enter thread.
Save image.
Leave thread.
>>
>>13098473
My friend has one who also watches anime. I'm jealous to say the least.
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>>13109719
>>
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Good thread.

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thread
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>>13109807
can it make my dick grows 5 extra inches?
>>
>>13109814
>>13109817
Back to /x/ retards

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Is the northern US and Canada the best place to buy land if you want to avoid climate catastrophe?
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>>13108356
Looks like Italy took up jogging and lost weight
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>>13107252
>You can't question them but I say they're questionable to refute you but still they're unquestionable.
Don't you get nauseous from all the doublespeak you're doing?
>>
>>13108356
>Denmark, the Netherlands and the entire state of Florida of will cease to exist
If anything ever destroys the netherlands, it won't be water. They'll just build more fucking dams.
>>
>>13108356
Sea levels are projected to increase less than 2 meters by 2100.

Climate change is severely overhyped.
>>
>>13105930
you posted a graph from 2010 and those are articles from this year.

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Judson or Pinter?
Shilov or H&K?
3 replies omitted. Click here to view.
>>
>>13107648
I'm taking Abstract Algebra this semester and so far Rotman's book has been good, it's both rigorous and easy to read. For practice problems I've been using Herstein's "Topics in Algebra".

As for introductory Linear Algebra, I'd go with Friedberg. It has a good balance of theory and applications and it's very readable. I think Shilov is a bit too dense. Hoffman it's a classic but probably a little difficult for a first course in Linear Algebra. Either way, it's always good to learn from different sources :)
>>
>>13107782
Do you mean Advanced modern algebra or An introduction to the theory of groups?
>>
>>13107610
go with pinter if you aren't a maths student but want a solid introduction
obviously augment thsi with more stuff afterwards but pinter is really good for getting your feet wet
>>
Bump
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>>13107610
Any more suggestions? More materia?

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>had the chance to join top STEM programme
>imposter syndrome
>enrol in BLaw
>graduate with a law degree
>switch to an MSc in business analytics in the hope of breaking into STEM
>still feel miserable
>thinking about switching to an undergrad program in CS

What can I do bro/s/? I'm 26 and feel like my life is already over.

I didn't believe in myself when it mattered and now I feel I lost out. I was admitted to a program I wanted to go and chickened out because I was scared.
Should I go for the CS or math undergrad and graduate with 29? Or should I work first and code on the side?

I feel lost and thought we might get our own support group going on /sci/ because there might be more of us here.
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>>13060063
Literally every adult in my life told me it's the way to go
>>
>>13098532
same age, but graduated at 24 so i only have a year not counting internships. everything at both big tech and small web app startup was profit or cost motivated that i really felt like i was just a glorified maintenance tool for the bean counters. it was existential enough that i convinced myself that i HAVE to become a research eng or RS somehow so that i didn't feel like i was wasting my life. if i wanted to waste my life i should become a neet on autismbux or a lazy government worker
>>
>>13106593
yes, the only good thing about the phd - 4 years of state money (now 3 left)
>>
>>13106182
PhDs are honestly overrated in their difficulty.

If you find a niche field where you can specialize, you usually don't have the same issues as in a Master's program, which is basically just studying a lot of different things, even if they're related.
>>
>one and a half years left of memechanical engineering
i dont want to do this anymore bros

any field of mathemathics i can use to produce realistic spacing and timing for animation of legged creaturee, organic and mechanical stuff doing walks or acting?

mostly just their legs and body being in the right position with the right timing relative to their body mass and the environment...
>>
>>13107696
be sure to ask this on /g/ as well, just in case someone there has experience with software that might be using what you're looking for,
>>
>>13107696
cascadeur is memed on hard but it might be what you're looking for
>>
>>13107696
Inverse kinematics

About to start college in the fall for math, plan on going into actuary work
Any actuaries here? Need to know if this is a good choice or if I’m setting myself up for a life of bullshit
>>
>>13109380
Shut up nerd
>>
Not an actuary but a friend from college is and my dad observed/worked with actuaries in the pharma industry. This is my personal opinion, if you like math it's a good way to make money doing math so you don't have to be a professional academic or a barista. Starting salary around $80k and companies have to pay you more when you complete your exams. It's a lot of fucking math. Lots of prob stat. You're calculating insurance premiums based on your models.

My dad thinks the entire profession shouldn't exist and that it's a lot of BS but he was working with people that started with desired outcomes and pulled data out of their ass to match the outcome. He didn't think any of them were useful to the company, much less competent at what they do.

I have no idea what a career path looks like for an actuary other than these anecdotes, so you could talk to some people to find out.
>>
>>13109380
The only person I know that got an actuarial degree passed all of his exams and wound up working as a tutor at a sylvan learning center in his late 20s. It’s already been replaced by programs.
Unironically learn to code.

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I intend to spend a set amount of time living without many of the things that define modern life, such as media and electronic devices (only to be used for actual work).
In a nutshell I'll spend my days lifting weights and other forms of exercise, reading only physical books, spend as much time in nature as I can, only play music instead of listening to music and so on.
The question then is how do I go about documenting results? What questions can I ask on a daily basis?
All input and other ideas on what I might spend my time doing are welcome.
1 reply omitted. Click here to view.
>>
>>13108684
Not really, more how to evaluate what if any effect this change in lifestyle actually has.
>How do I feel from 1-10?
Seems rather arbitrary.
>>
>>13108674
measure what you do in the time and how consistent you are. once you stop, see if you regress to your old habits
radically changing your lifestyle often leads to burnout
over the past 3 months i only successfully built 2.5 habits. maybe i'm just built to be lazy
>>
>>13108692
i suppose just figure out what you want to measure in yourself against the means you have to do so.
i assume you don't have a lab so that rules out any biological measurements like blood etc.
so all you are left with are external measurements:
resting heartrate
quality of sleep
basic psych measurements like happiness etc.
you could also write about how the lack of electronics and media are impacting your socialisation.

i mean, what is your purpose in doing this? just quanitfying to yourself about how you feel now compared to how you'll feel in a year?
>>
>>13108674
I think the metric most people use in this type of experiment is # of girls slept with. You could also track weight you can lift. And books read.

Everyone knows this leads to a healthier, happier life. That doesn't matter, though, since most people won't do it. Even the way you're going about setting of to do it is through first attention seeking rather than just doing it. If it helps you to have a framework of scientific experimentation, track blood pressure, heart rate, and yes, how you feel. However, at the end of the day it's just you living a life you think will make you more fulfilled. You aren't doing this on 1000's of people. You aren't tracking bio markers. This is for you, and you'll know how you feel 6 months into it.
>>
>>13108674
Keep a calender, and every day before bed draw a smiley face or a sad face for that day

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>be me
>age 5
>teacher walks up to me
>anon how did you get that answer
>tell her I did it in my head
>HFW
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>>13107253
Some people still can do it in their head, but teacher's require you to show work in order to spot the cheating googlers.
>>
>>13107253
>tell her I did it in my head
even a five year old should understand why this isn't an answer
>>
>>13107569
Retards like this guy think it's impossible for a cheater to copy down the workings.
>>
Because jotting math as fast as possible with your right hand (for me) feels really good and explodes my intelligence neurons. Something about double left brain activation I think.
>>
>why don't X
They do

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It looks like shit
It looks like a half inflated Mylar balloon
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>>13108802
>nooooooooooo you can't have your rockets look like silos they need to look modern and shit Thundercuck said so reeeeeeeeeeeee
>>
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>>13108810
it's purpose is to make bugmen post on reddit
>>
>it looks so fake it has to be real
If it looks like a blimp, if it goes up like a blimp and the “owner” of the company tells you he wants you to believe things are real, if they look fake - maybe it’s just the way it looks.
>>
Was it launched? Any footage of it's use as field testing available.

like yeah it looks like shit but like >>13108810 said.

Or maybe that's a flat-earther's rocket that's why its so shitty.
>>
>>13109324
Sometimes it’s a model or a hologram (they found projectors at the NASA lawn). Or it’s the good old blimp https://youtube.com/watch?v=utjnBClBMHY

Is it real?
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>>
Telegony isn’t real in humans
>>
>>13108757
Because you say so?
>>
fake and gay
>>
God, these threads are so fucking cringe, mods delete ffs
>>
If it's true, does that mean that you can have a child with 3+ parents?

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This is one of the greatest /sci/ happenings in the last years, both for geologists, physicists and european technology in general.
Why?
Because this new deposit discovered in Germany spanning in an heterogeneous way roughly from Frankfurt to Southern Freiburg (and not too far from Basel (CH) and possibly continuing below Switzerland too) will allow the german and european electric battery industry to eliminate dependence from raw materials originating in America, China and Africa.
Also this discovery is a golden ticket for when the world will have developed fusion energy, since lithium can be used as fuel.
We're talking about 40000 tons of lithium hydroxide each year (to begin with).
This single major discovery just put (back) Europe on the same geopolitical scale as the U.S. and China. If you don't believe me now, you will in some years.

Sources:
https://deepresource.wordpress.com/2021/04/08/germany-could-be-sitting-on-large-lithium-reserves/
https://onlinelibrary.wiley.com/doi/full/10.1111/gfl.12122
https://blog.adafruit.com/2021/05/04/massive-amount-of-lithium-discovered-in-the-rhine-river-valley/
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>>13103965
She cute, I would give her my discarding sabot penetrator if you catch my drift.
>>
>>13109114
luckily there's us to defend them against evil ruskies and chinks, they just have to pay a racket.
>>
>>13109020
>duopolies
Oligarchies. A lot of them have 4 big dogs rather than 2 of a duopoly. But yeah, good reminder not to keep more than 40% of your portfolio in Australian companies even if you are an Australian.
>>
>>13109126
Europe literally has to pay protection money to the ZOG, what a shit time to be alive in.
>>
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Nice, chinknoids btfo

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Chemistry is fun
> mix a weak based solution with a pKa=9.2 with another weak based solution with pka=9.197, C=1,4 mmol/L and V=25mL
> the product's pH is 10.495
> Find τf of the product
I regret choosing chemistry
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>>13106817
Imagine. People on this board really are posting that they have a "163 IQ" and then get filtered by Gen. chem. What a world.
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>>13104069
>TAing general chemistry
>"My calculator can't do that" (scientific notation)
>"what is a log?"
>"I forget the quadratic equation"
Never again.
>>
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>>13106988
Fuck bro. I literally had to teach someone how to add fractions.
>>
got any advice for making alkyl nitrites? I bought some glassware and tools to make some, but i'm kinda having trouble sourcing the actual materials(specifically the alcohols. Isopropl is very easy to find, but i dont wanna go blind, so amyl or butyl would be pref.)
>>
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>>13107451
Make some spirits like rum or vodka but keep the higher boiling point fractions (fusel alcohols). You can add L-Leucine to the ferment to increase the proportion of isoamyl alcohol produced, as that's the one that you want. Separate it and the isobutyl alcohol by fractional distillation using your proper glassware.




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