Quantcast
[ 3 / biz / cgl / ck / diy / fa / g / ic / jp / lit / sci / tg / vr ] [ index / top / reports / report a bug ] [ 4plebs / archived.moe / rbt ]

2017/01/28: An issue regarding the front page of /jp/ has been fixed. Also, thanks to all who contacted us about sponsorship.

/sci/ - Science & Math

Page 2


View post   

[ Toggle deleted replies ]
File: 34 KB, 557x356, 719582-3-4IP1.png [View same] [iqdb] [saucenao] [google] [report]
9315068 No.9315068 [Reply] [Original] [archived.moe]

Anyone here familiar with computer architecture? I have a question and I'm not exactly sure how to go about solving it.

" Consider a hypothetical machine with a byte-addressable main memory of 2 Mbyte
and a block size of 32 bytes. Assume that a direct mapped cache consisting of 32
lines is used with this machine."

How many Bytes in total can be stored in the cache? I can't seem to wrap my head around finding the process to answer this

4 replies omitted. Click Reply to view.
>> No.9315131 [DELETED] 

>>9315068
direct mapped = 1 way per line = 1 block per line
32 lines of 32 bytes each = 1024 bytes

>> No.9315146

>>9315068
got a bit confused about diff between line block and set. apparently line = block. glad i cleared that up.
good thread op,
anyways 32 blocks of 32 bytes each = 1024 bytes.

>> No.9315183

>>9315146
A line is not a block.

A block is the unit in which data is transferred to and from the main memory. A cache line may or may not have the same size as a block. It's a sensible and common structure, to be sure, but not the only possible one.

A "direct mapped cache" is one in which cache lines directly correspond to blocks, so in this particular case a block has the same size as a cache line. But other forms of cache also exist.

>> No.9315192

>>9315183
you are using "cache line" the way most people talk about "cache set"
but when you search online you see people talking about a cache set containing multiple lines

>> No.9315213

>>9315068
You need save the address of the cache line which needs to be able to address the memory log2(2M)=21 bits. So you have 32 lines * 29 bytes remaining per line = 928 bytes.



File: 10 KB, 236x213, 1511369907680.jpg [View same] [iqdb] [saucenao] [google] [report]
9315053 No.9315053 [DELETED]  [Reply] [Original] [archived.moe]

>tfw only 110 I.Q (actually tested by a doctor)

>ADHD

Can I ever go to a UNI? Or get a high paying job? STEM is out of the question for me, so what would be the next good thing? Accounting is in high demand and is pretty easy compared to STEM and pays close to STEM degrees, right? Could I even do accounting with my I.Q? I'm very nervous for my future and I'm considering becoming a full shut-in NEET after HS becuase of my I.Q. Is anyone here going to a Uni or doing STEM with a low I.Q and actually passing?

4 replies omitted. Click Reply to view.
>> No.9315193

>>9315053
>Accounting is in high demand and is pretty easy compared to STEM and pays close to STEM degrees, right?
Why waste our time asking a simple question like this when you could just Bing™ it?

>> No.9315194

>>9315168
t. 105 iq brainlet

>> No.9315206

Just become an engineer

>> No.9315210

>>9315175
Nothing really. 1 point differences wouldn't matter.

>> No.9315214

>>9315206
You need at Least a 125-130 I.Q to be an engineer. You'd probably have a hard time to find any actual engineers with a sub 120 I.Q



File: 34 KB, 408x450, Q5ptlCx.png [View same] [iqdb] [saucenao] [google] [report]
9315044 No.9315044 [Reply] [Original] [archived.moe]

What did you learn today /sci/? You did learn something new today... right?

Today I learned 15 new kanji, 20 new vocab words, played guitar, and did some geometry. I could have done more but I my focus is fucked because my grandmother went to the hospital this morning. Excuses, I know.



File: 81 KB, 1000x667, 1481279311395.jpg [View same] [iqdb] [saucenao] [google] [report]
9315015 No.9315015 [Reply] [Original] [archived.moe]

So I've been thinking about string theory, how everything is waves, and consciousness.

Interaction between matter is waves. Energy is waves. Is consciousness and thoughts just waves as well? Is it energy and matter? Or can it exist outside of string theory? Light is seen by the eyes, sounds are heard, and then it's processed in the brain. But then also there is some experience. What do you anons think consciousness really is? What are thoughts? I can 'feel' thoughts like they are some kind of object in my head but it's so weird.

Is consciousness some kind force or property that the brain receives and interacts with? That's my current theory

18 replies omitted. Click Reply to view.
>> No.9315140

>>9315136
>It's apparent from this thread I know more than any of you will ever hope to know
Then post your string theory publications. If life goes well for me, I'll publish some eventually. If you know more than I ever hope to, golly goodness you better have some dope af papers published.

>> No.9315148

>>9315140
I know the basics of string theory, but that's not what I'm concerned with. I only mentioned it because it's the most comprehensive model of reality we have. I don't need to know the finer details. I'm concerned with the nature of consciousness and how it fits into the model of everything essentially being vibrations.

Actually if I'm wrong on that point I'd like to know, maybe my understanding of it is wrong.

>> No.9315166

>>9315148
Look, I'm sorry for being a dick. That's on me. It sounds like you're legitimately curious and not just stoned out of your mind.

Let's talk about models. The atomic model (protons, neutrons, electrons) is fantastic for chemistry. Everything works and life is a breeze. However, if you look too hard at the protons you begin to get problems.
So we make a new model that explains what the protons are made of, and everything is good. Then a bunch of people get agitated and we come up with the string theory model. All well and good.

Given this, if you wanted to do chemistry would you use the atomic model, the model with quarks and shit, or string theory? Clearly you'd use the atomic model because to do (most) chemistry you don't need to know jack about what's going on inside the protons. If the atomic model being "wrong" bothers you, remember that every model we have ever had, ever is just as "wrong." All models have ranges of validity when you can sensibly apply them. Most of the models we're familiar with are pretty useful. They're like tools.

The reason you're getting so much flak in this thread is that you're trying to apply a very big thing (consciousness), to a very small-scale model (string theory). Describing consciousness in the context of string theory would be like trying to build a building using only tweezers. Tweezers are very useful, but not for something like construction. This is the same reason that chemists don't talk (very much) about quarks. Sure they exist, but for what they're doing it doesn't matter whether they exist at all. In order to mix Hydrogen and Oxygen to make water, you don't need to know about quarks.

In this same way, trying to explain consciousness with string theory is pointless. Just like it's pointless for a chemist to keep track of every quark and virtual particle in their test tube. For the chemist, the atomic model works perfectly fine. To explain consciousness, you probably don't even need something that small.

>> No.9315203

>>9315166
Ah I see. I've been overthinking this stuff. I can't stop thinking about it admittedly. How everything in reality relates to each other. But consciousness seems to not quite fit with everything else, or at least it seems that way to me.

Like particles vibrate, they create matter and energy, which interact and create a universe, the universe reacts with itself and here we are. But then somehow consciousness or a sense of experience arises out of all that. We're not just robots acting and reacting mindlessly (or perhaps we are). Anyway I haven't had much sleep which is why this all seems like a drug induced rant as one anon said

>> No.9315256

>>9315074
>String theory is currently the best model for reality
how?



File: 13 KB, 620x349, 1440769500370.jpg [View same] [iqdb] [saucenao] [google] [report]
9314997 No.9314997 [Reply] [Original] [archived.moe]

>If I just ignore Hume's Law, it doesn't exist

Wow, truly the greatest thinker of this generation.

18 replies omitted. Click Reply to view.
>> No.9315238

>>9315085
Passing the buck. Why ought one seek the greatest pleasure for everyone?

>> No.9315271

>>9315128
it's daniel radcliffs less successful uncle

>> No.9315273

>>9315238
because that maximizes your personal enjoyment of life

>> No.9315276

even if morality exists only with an observer, the observer can just be the concept of morality in of itself. it can be self aware.

>> No.9315306

>>9315182
Just because something doesn't exist objectively doesn't mean it does not exist. Our perceptions are literally everything. If I convince my coworkers that my boss raped me, and the perception is that he raped me, then he is a rapist. You're arguing that morals exist when they already do on an intersubjective level.



File: 1.81 MB, 2000x1319, engineering-blueprint.jpg [View same] [iqdb] [saucenao] [google] [report]
9314987 No.9314987 [DELETED]  [Reply] [Original] [archived.moe]

Should I major in chemical engineering or electrical engineering? What books would you recommend?

4 replies omitted. Click Reply to view.
>> No.9315038

>>9315003
Do ChemE's actually learn that much chemistry in school?

>> No.9315050

>>9315038
Nah, but you should.

>> No.9315057

>>9315037
I wanna find new efficient ways to produce CLEAN electricity... I like this planet

>> No.9315060

>>9315057
But we already have them?
You're like a century too late.

>> No.9315066

>>9315060
Better solar panels and windmills. I've always been interested about electricity since I was in 3rd grade



File: 65 KB, 800x600, serveimage (16).jpg [View same] [iqdb] [saucenao] [google] [report]
9314980 No.9314980 [Reply] [Original] [archived.moe]

How to become a good detective, /sci/?

1 replies omitted. Click Reply to view.
>> No.9315013
File: 124 KB, 882x731, 1494120939675.jpg [View same] [iqdb] [saucenao] [google] [report]
9315013

>> No.9315023
File: 1.04 MB, 1828x2580, PD.jpg [View same] [iqdb] [saucenao] [google] [report]
9315023

>> No.9315043

>>9314980
>critical thinking
>problem solving
>attention to detail
>some degree of computer skills and knowledge of technology
>good written and oral communication skills
>pateince
>knowledge of the law
>means of self-defence
and that's just the basics

>> No.9315100

>>9315043
>>critical thinking
How would one practice critical thinking?

>> No.9315122

>>9314980
>>>/lit/ would be of better help unironically



File: 21 KB, 236x315, image.jpg [View same] [iqdb] [saucenao] [google] [report]
9314956 No.9314956 [Reply] [Original] [archived.moe]

What is the easiest thing from your field of study that can be mastered in two weeks and has considerable practical application?

>> No.9314968

>>9314956
Mech engi here
The basics of MATLAB can easily be learned in 2 weeks of straight study and now you have a calculator on steroids that help you solve repetitive problems without quickly.
It comes with a bunch of other stuff to, like Simulink, which might be useful but I haven't used it for anything yet.

>> No.9314982

>>9314956
PhD Synthetic Organic Chemist.

Proton NMR.



File: 64 KB, 720x594, 1501909849650.jpg [View same] [iqdb] [saucenao] [google] [report]
9314954 No.9314954 [Reply] [Original] [archived.moe]

Say our universe is a simulated reality by some supercomputer, would it eventually be possible through our simulated physics to escape/leave that simulated reality into the supercomputer's reality?

4 replies omitted. Click Reply to view.
>> No.9314993

>>9314954
Yeah dude, that's what happens when we die.

>> No.9315018

>>9314954

What does the fox say?

>> No.9315314

>>9314954
Your consciousness would require a vessel to inhabit in that higher reality. Technically, since you are being simulated on the computer, you are already inhabiting a vessel. You just don't have sensory input or a body to interact with that higher reality in a direct manner.
Your experiences in the simulation might depend on a stream of external information from the higher reality, but they could also just be from a closed simulation that isn't fed any external input. Basically, you might already have some sort of sensory input from that higher reality.
As for acting in that higher reality, there may be beings observing what you do in the sim and taking actions in the higher reality based on what you are doing. They might not even be intelligent beings. They might just be actuators that take the data from your sim and simply decide to steer left or right.

Is 1 neuron conscious? Is a neuron that is connected to a photo-receptor conscious? Is a neuron that tells a muscle fiber to fire conscious? Do the experiences of a single neuron even remotely resemble those of the aggregate consciousness?

You might just be a neuron whose entire reality is just the interactions between you and the neighboring neurons. You don't know how the inputs from the higher reality manifest in your experiences and you don't know how your outputs manifest in the output of the vessel you inhabit.

>> No.9315324

>>9314954
Can minesweeper escape Windblows and put a flag in your ass?
Nope.

>> No.9315330

>>9314954
>leave that simulated reality into the supercomputer's reality?
DMT



File: 368 KB, 2000x1332, Work-Experience.jpg [View same] [iqdb] [saucenao] [google] [report]
9314938 No.9314938 [Reply] [Original] [archived.moe]

PSA: Intelligence takes second place to experience.

Brains btfo, hippocampus #1 campus. get rekt smart fags.

>> No.9314944

>>9314938
Good thing thanks to my autism, I have both.
*flex*
>tfw when a braingain and memgain



File: 65 KB, 500x375, 1502422744006.jpg [View same] [iqdb] [saucenao] [google] [report]
9314933 No.9314933 [Reply] [Original] [archived.moe]

What does observer mean in quantum mechanics speak? I always hear about about things possibly existing in multiple places but being forced to take a position when observed but what exactly is an observer in this case?

>> No.9314936

>>9314933
usually a machine taking a measurement of a value of some property of whatever it's looking at.

>> No.9314939

>>9314936
Typically that measurement is made by bouncing a photon off the particle theyre measuring



File: 15 KB, 250x243, frog2.jpg [View same] [iqdb] [saucenao] [google] [report]
9314920 No.9314920 [Reply] [Original] [archived.moe]

why does every person have a mild form of OCD?

>> No.9315076

Because otherwise you'd have attention deficit disorder. It's a scale, like anything else. There's a sweet spot where you get interested in something and get it done. There are extremes, where you can't get interested enough to get anything done or obsess about perfection so much you can't get anything done, or get into diminishing returns territory. Extremes are usually bad. Find your sweet spot and don't worry about it.

>> No.9315124

sometimes I pretend to be OCD, like aligning something with a table, just to appear normal



File: 779 KB, 2361x1109, Capture.png [View same] [iqdb] [saucenao] [google] [report]
9314901 No.9314901 [Reply] [Original] [archived.moe]

do you guys think the top two graphs of the left follow the trend of the red line on the bottom?

k thx

>> No.9314903

no idea

>> No.9314906

install gentoo

>> No.9314912

1. install R

2. stop plotting so many lines in one graph

>> No.9314934

Okay if each x is a separate element then why are you connecting the points. It’s misleading, graph the differences instead.



File: 167 KB, 800x600, 93c.jpg [View same] [iqdb] [saucenao] [google] [report]
9314890 No.9314890 [Reply] [Original] [archived.moe]

https://en.wikipedia.org/wiki/Timeline_of_the_far_future

>The Universe's expansion causes all galaxies beyond the former Milky Way's Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.[89]

>High estimate for the time until normal star formation ends in galaxies.[4] This marks the transition from the Stelliferous Era to the Degenerate Era; with no free hydrogen to form new stars, all remaining stars slowly exhaust their fuel and die.[3]

>By this time, if protons do decay, the Black Hole Era, in which black holes are the only remaining celestial objects, begins.[3][4]

>On this timescale, any discrete body of matter "behaves like a liquid" and becomes a smooth sphere due to diffusion and gravity.[99]

>Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease.[6]

>Around this vast timeframe, quantum tunnelling in any isolated patch of the vacuum could generate, via inflation, new Big Bangs giving birth to new universes.[103]

14 replies omitted. Click Reply to view.
>> No.9315159

>>9315149
>Who cares? We will never be able to leave the galaxy anyway. All that nonsense is unreachable.
Wrong, we could, in theory, go to anywhere within the Local Group as it is gravitationally bound.

>> No.9315171

>>9314890

Let's say we die. If you don't exist anymore doesn't everything that the universe is or will do pass instantly until your next instance of existing again? Since you cannot perceive the state of existing anymore the rest of the universe should be reduced to a state you no longer experience. It still acts upon itself while you aren't in it but you can only experience the universe existing while you do right? even if infinite time passes shouldn't the moment we stop existing and start existing again be an instant? and if time really is infinite doesn't that mean all possibilities including existing again will happen?

>> No.9315178

>>9315118
>won't die
sure buddy

>> No.9315180

>>9315171
>your next instance
even if it's an atomwise copy of you, it won't be you

>> No.9315218

>>9315149
lul3d, not only is it possible to travel to any point within our local group at sublight speed its extremely probably because humans dgaf and will do whatever they think is cool



File: 92 KB, 720x983, IMG_20171122_203628_3358.jpg [View same] [iqdb] [saucenao] [google] [report]
9314844 No.9314844 [Reply] [Original] [archived.moe]

Hmmm?

>> No.9314878

>>9314844
wtf is with those lin
es ending without a
ny dashes or at lea
st better spacing?



File: 80 KB, 1920x298, Screen_Shot_2017-11-22_at_9.34.37_PM.png [View same] [iqdb] [saucenao] [google] [report]
9314843 No.9314843 [Reply] [Original] [archived.moe]

Why haven't you published to a scientific journal yet, /sci/?

>> No.9314883

>>9314843
What's that nonsense?

>> No.9314889

>>9314843
I have

>> No.9315029

>>9314843
My H index > yours

>> No.9315031

>>9314843
But I have...



File: 146 KB, 590x797, preview.jpg [View same] [iqdb] [saucenao] [google] [report]
9314825 No.9314825 [Reply] [Original] [archived.moe]

Is mathematics entirely circular logic? I haven't taken much math (compsci major so not brainlet tho), but does math have any physical foundation or is it all manipulating symbols that we've made up?

33 replies omitted. Click Reply to view.
>> No.9315279

>>9314825
>Is mathematics entirely circular logic?
This question is absurd.
>does math have any physical foundation
>>9314830
Also, how many fingers do you have?
> is it all manipulating symbols that we've made up
>compsci major so not brainlet tho
>compsci major
>so brainlet tho

>> No.9315429

>>9314825
It is the compression of many truths into just a few axioms or the decompression of the axioms into the many truths.

It is similar to law or religion where you start with a list of all of the goods and bads and characterize them by a smaller list of rules.

In all of these cases we do it backwards where the list of rules is sacred and everything that follows is sacred whether we like the conclusion or not.

>> No.9315437

>>9314849
>claims to be CS brainlet
>doesn't know what recursion is

>> No.9315440

>>9314825
you needs to do some more reading anon:
https://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.html

>> No.9315442

Analysis is the blueprint for precision that can be used to build many things in a smooth continuous manner

Algebra is the blueprint for mapping a structure in space and relating its structure to the space it surrounds and occupies.

They connect to reality in a way that is not specific because the world is a big place with many rare things. Look up books on non associative algebras or nonlinear pdes. Math has to be generalized to touch these areas equally. The price for generality is abstraction.



File: 15 KB, 600x600, ua.png [View same] [iqdb] [saucenao] [google] [report]
9314820 No.9314820 [Reply] [Original] [archived.moe]

You are inside a box in a universe with nothing in it. The box keeps accelerating for whatever reason. It accelerates until it reaches light speed. How do you know the precise time at which the box reached light speed?

22 replies omitted. Click Reply to view.
>> No.9315379

The box would elongate toward the direction of travel indefinitely as you reach the speed of light. You would know you have reached it when the box appears to stretch for infinity. Time for you would stop once you hit the speed of light, so when the box stops elongating is another way to tell when you've reached it.

>> No.9315445

>>9314820
The speed limit is not defined for space outside of the universe. The acceleration could have happened without time, it's possible because it's outside of the ordered field.

>> No.9315448

>>9314841
But isn't the box an exclusion where infinity couldn't have been defined?

>> No.9315468

>>9314852
That's something entirely different. We could take x as an element of space and z as an element of time. Then we would take a as a variable and formulate it as (x/z)^a. The acceleration is described as the derivation function.

>> No.9315470

>>9315222
That would be the case if we were talking about particles



File: 369 KB, 750x894, 1445271B-5694-4DAB-B8C0-B20745D27D8D.jpg [View same] [iqdb] [saucenao] [google] [report]
9314819 No.9314819 [Reply] [Original] [archived.moe]

Just imagine where we would be in terms of space development had we not chickened out on this.
>8 million ton spaceships

>> No.9314937
File: 99 KB, 336x296, coyote.png [View same] [iqdb] [saucenao] [google] [report]
9314937

>>9314819
>Just imagine
I grew up on roadrunner cartoons, I know exactly how this ends.

>> No.9314946

>>9314819
If we managed to do it safely?
Mhm... but no nukes in space, because of the law. Thank you, Cold War.

>> No.9314947

>>9314946
This. Fucking Communists.

>> No.9314976

>>9314819
Wait, is this legit? Were these designs ever verified? 6,000 Isp is ridiculous huge. 100,000 is unimaginable.



File: 314 KB, 1000x1271, 1510797266138.png [View same] [iqdb] [saucenao] [google] [report]
9314761 No.9314761 [Reply] [Original] [archived.moe]

What's ZFC?

11 replies omitted. Click Reply to view.
>> No.9314888

>>9314886
I think, therefore I am.

>> No.9314952

>>9314834
>>he's doing it again! haha, what a madman!
I'm not a "he".

>> No.9314953

>>9314834
>>he's doing it again! haha, what a madman!
Who are you quoting?

>> No.9314960

>>9314882
>But you can't prove it is consistent. Shit theory.
Conjectures are natural in mathematics though, might as well get used to it

>> No.9314992

>>9314882
if you could prove it's consistent, it wouldn't be.



View post