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Wednesday, March 13, 2019

AskScience AMA Series: I am Dr. Nina Kraus and will talk about how music and concussion impact brain health. Ask Me Anything!

AskScience AMA Series: I am Dr. Nina Kraus and will talk about how music and concussion impact brain health. Ask Me Anything!


AskScience AMA Series: I am Dr. Nina Kraus and will talk about how music and concussion impact brain health. Ask Me Anything!

Posted: 08 Mar 2019 04:00 AM PST

How do our experiences, such as learning how to play music and playing sports, affect our brain? Although we are surrounded by sound all of the time, we rarely give much thought to this invisible yet powerful companion. The auditory system is a uniquely complex sensory system and the ability to make sense of sound relies on exquisite precision by the brain. Given the complexity and precision of the auditory system, accurate sound processing is particularly vulnerable to head injury. On the other hand, its precision can be honed by activities that exercise the auditory brain such as playing a musical instrument.

We have discovered a way to objectively capture the imprint that sounds leave on our brains. This biological approach empowers us to learn more and more about this invisible ally and enemy of brain health. Dr. Kraus will examine the promise of measuring soundprints in the brain to assess and manage sports-related concussions. She will discuss how music training is beneficial for the brain, strengthens our communication skills, and can inform health care, education, and social policy.

Dr. Kraus will be here at 2:00 CT (3 ET, 19 UT). Ask her anything!

Links:

articles: Kraus N, White-Schwoch T (2017) Neurobiology of everyday communication: what have we learned from music? *The Neuroscientist(. 23(3): 287-298.

Kraus N, Nicol T (2017) The power of sound for brain health. Nature Human Behaviour. 1: 700-702

Kraus N, Thompson EC, Krizman J, Cook K, White-Schwoch T, LaBella CR (2016) Auditory biological marker of concussion in children. Nature: Scientific Reports. 6: 39009.

submitted by /u/AskScienceModerator
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Can you use a regular compass on Mars?

Posted: 12 Mar 2019 02:15 PM PDT

AskScience AMA Series: I am Professor Kartik Hosanagar and I'm here to discuss how algorithms and AI control us and how we can control them. Ask Me Anything!

Posted: 13 Mar 2019 04:00 AM PDT

Through the technology embedded in web-enabled devices, algorithms and the programs that power them make a staggering number of everyday decisions for us, from what products we buy, to where we decide to eat, to how we consume our news, to whom we date, and how we find a job. We've even delegated life-and-death decisions to algorithms-decisions once made by doctors, pilots, and judges.

In my new recently published book, ``A Human's Guide to Machine Intelligence: How Algorithms Are Shaping Our Lives and How We Can Stay in Control'', I have surveyed this brave new world and revealed the potentially dangerous biases they can give rise to as they increasingly run our lives. I make the compelling case that we need to arm ourselves with a better, deeper, more nuanced understanding of the phenomenon of artificial intelligence. I have examined episodes like Microsoft's chatbot Tay, (which was designed to converse on social media like a teenage girl, but instead turned sexist and racist), the fatal accidents of self-driving cars, and even our own common, and often frustrating, experiences on services like Netflix and Amazon.

I will be available fro 3-5PM ET (19-21 UT). Ask me anything!

submitted by /u/AskScienceModerator
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Is it possible to give a planet without an active core a magnetic field?

Posted: 13 Mar 2019 04:48 AM PDT

I'm mostly thinking of Mars, inspired by a top post in this sub about compass use on the planet. I know the reason Mars is barren is it's lack of a protective magnetosphere, but could the planets core be jump started or an artificial field be developed? Obviously both require vast amounts energy but let's pretend such energy is available for said purposes.

submitted by /u/DarthReeder
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How are various sea creatures such as dolphins and whales, able to "hold their breath" for so long under water?

Posted: 13 Mar 2019 01:25 AM PDT

What is different about their physiology that allows them to stay under water for so long?

submitted by /u/Sol33t303
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How do aeroplane black boxes withstand crashes which otherwise destroy the plane and everything inside of it?

Posted: 12 Mar 2019 02:49 PM PDT

I get that they are built to a higher specification, but not how that is achieved.

submitted by /u/mattjstyles
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Are drops of water consistent in size? How big is that, and why? And what about other substances like oil, or molten metal?

Posted: 12 Mar 2019 04:04 PM PDT

“Wigner’s Friend” thought experiment — How does this suggest objective facts don't exist?

Posted: 13 Mar 2019 06:06 AM PDT

I understand that according to the laws of quantum mechanics, the photon exists in a superposition until it's measured.

If Wigner's Friend measures it and Wigner doesn't, doesn't Wigner just have a lack of information? Wigner hasn't taken the next step to get the answer. Can his friend measure the polarization and get a different result each time? I'm having a difficult time reconciling how this is different than if Wigner looked into the distance and couldn't give a measurement for where the horizon disappeared, but his Friend could because he DID measure it. His Friend has more information — it doesn't mean objective facts don't exist. I have to be missing something super simple here or the experiment wouldn't have credence. I'm not trying to say it's wrong I just don't understand.

submitted by /u/Ikioi
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Do insects need to sleep too?

Posted: 12 Mar 2019 04:57 PM PDT

As in, does the mosquito that pesters me when I sleep need to sleep as well or do small lifespans of some insects means they die before they need to sleep (if they do sleep).

submitted by /u/LeNerdNextDoor
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Why do some quantum interactions cause entanglement, and some interactions cause wave function collapse?

Posted: 12 Mar 2019 11:22 PM PDT

Two particles interacting can enter a superposition / become entangled.

But also, some interactions are an observation / measurement that cause wave function collapse.

How does this work? What's special about 'observations', why don't they just become entangled with the system rather than causing wave function collapse?

submitted by /u/imMAW
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If carbon dioxide is only 0.0391 percent of the atmosphere, how does it have such a big impact on climate change?

Posted: 12 Mar 2019 02:22 PM PDT

Hi everyone, I have a teacher who believes that humans are not to blame for climate change and that climate change is not a real thing due to the fact that carbon dioxide only makes up a very small part of the atmosphere. I have tried to research this, but found conflicting results. Can you please help me to find an answer?

submitted by /u/Wavymiik
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Can the new fission reactor designs completely guard against nuclear meltdowns?

Posted: 13 Mar 2019 04:58 AM PDT

Hi all,

I hope some of you can clarify a discussion I had with a colleague. We talked about the safety of Nuclear Fission Reactors. And my colleagues contention is that the new fission reactors are completely safe. That they can't melt down. Which I highly doubt.

His argument is that the new reactors are designed to remove fuel materials from one another, and thus stopping the reaction (as opposed to fuel control rods), and that by removing the fuel material from eachother would cause the fuel to stop generating heat, and thus would never get hot enough to melt the material.

But my counter is that the residual heat from the fuel elements would be enough to melt the fuel material in case of a completely loss of coolant. Now I get that the newer tier IV reactor designs incorporate security measures, such as a closed loop system without the needing of pumps etc. - Which does make the design much more secure.

But can someone clarify whether a core meltdown can be avoided by separating the fissionable material even if there is a loss of coolant?

submitted by /u/Xenoxsis
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How to turn a sphere inside out?

Posted: 12 Mar 2019 11:49 AM PDT

I recently saw an animation in which they said mathematicians have figured out how to turn a sphere inside out. The material was stated to be an abstract elastic material that can stretch, bend and pass through itself.

The rules of the game were: - You cannot rip or puncture the material without destroying it. - You cannot crease or sharply bend the material without destroying it.

I wondered if someone could either explain the maths behind it or how the mathematicians came to the conclusion it was possible.

Here's the link to a similar video from Facebook: https://www.facebook.com/CymaticUniverse/videos/330251244444076/

submitted by /u/AtomicGeckoIII
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Are autoimmune diseases and allergies related? How do they differ?

Posted: 12 Mar 2019 04:07 PM PDT

Who invented or discovered the concept of mass as distinct from weight?

Posted: 12 Mar 2019 12:56 PM PDT

If all early science took place on earth where gravity is constant, mass and weight are seemingly interchangeable. So, someone at a certain point had to make the distinction between the two. It seems likely that this couldn't happen until after Newton. Did he discover this distinction? It doesn't seem completely necessary for him to discover this. F=ma looks a lot like F=wa when gravity is constant. This is a fundamental unit of science and the history of the distinction doesn't seem well documented based on some searching.

submitted by /u/lizzardman
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In massive stars, hydrogen fuses into helium, then carbon, neon, and oxygen before eventually fusing into iron. During the oxygen fusion phase, why doesn't all the oxygen simply ignite/catch fire?

Posted: 12 Mar 2019 01:59 PM PDT

The male hormone testosterone causes hair loss at males, but increases the beard growth. How does that work? Isnt hair=hair, no matter if in the face or at the head?

Posted: 12 Mar 2019 11:51 AM PDT

Are there any major cases of speciation/evolution in invasive species that we know of?

Posted: 12 Mar 2019 04:20 PM PDT

Are any invasive species known to have diverged substantially from original populations after years of isolation?

Obviously evolution is ongoing and continuous but what about obvious physical differences that are already the result of a species being relocated by humans?

submitted by /u/cncwmg
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[Physics] Spin - If I give Sally an electron in the morning, can I tell if Sally rotated an even number of times at the end of the day?

Posted: 12 Mar 2019 01:39 PM PDT

This is what my Naive pop-sci knowledge of spin tells me.

We would some measuring device that first measures some quantity ( call it electron-rotation) of the electron and then measures it again at the end of the day. We can only tell the difference between the number of rotations mod 720° though.

Now, a different question. If before measuring Sally, I grabbed my device and I did a 360° rotation. And then I measured Sally. Would it add 360° to the measured electron rotation?

So if I could paint electrons with rotation between 0°,360° as green, and 360°,720° as blue, then if I did a 360° rotation they would all swap colors right?

submitted by /u/TransientObsever
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How are modern processor architectures tested and refined?

Posted: 12 Mar 2019 10:06 AM PDT

How do counterweights at the tops of tall buildings such as a pendulum or pool of water counteract the buildings swaying?

Posted: 12 Mar 2019 10:02 AM PDT

Why do people say it’s the current that kills you and not the voltage?

Posted: 12 Mar 2019 10:24 AM PDT

Tuesday, March 12, 2019

How can a device on an aircraft or car be electrically grounded?

How can a device on an aircraft or car be electrically grounded?


How can a device on an aircraft or car be electrically grounded?

Posted: 11 Mar 2019 10:38 PM PDT

Is there a material? A static discharging pole maybe?

submitted by /u/okijhnub
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When you build a tolerance to alcohol, does your body get better at removing it, better at functioning with it, or just better at not feeling it?

Posted: 11 Mar 2019 07:30 PM PDT

Would a helium balloon rise faster in air or water?

Posted: 11 Mar 2019 09:31 PM PDT

The buoyant force in water would be greater but so would the drag. Anyone know the answer???

submitted by /u/KnuckleSniffer
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Why is the error term in the Störmer-Verlet method O(Δt²) and not O(Δt³)?

Posted: 12 Mar 2019 06:56 AM PDT

If positions at t + Δt are:

r(t+Δt) = r(t) + v(t) + ½a(t)Δt² + ⅙b(t)Δt³ + O(Δt⁴)

and for t - Δt the positions are given by:

r(t-Δt) = r(t) - v(t) + ½a(t)Δt² - ⅙b(t)Δt³ + O(Δt⁴)

And the subtraction of both equations results in

r(t+Δt) - r(t-Δt) = 2v(t) + ⅓b(t)Δt³ + O(Δt⁴)

Which is the same as

r(t+Δt) - r(t-Δt) = 2v(t) + O(Δt³)

Why is the velocity given by

v(t) = [r(t+Δt) - r(t-Δt)] / 2Δt + O(Δt²)

And not

v(t) = [r(t+Δt) - r(t-Δt)] / 2Δt + O(Δt³)

Thanks

submitted by /u/blackbat24
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If mouthwash supposedly kills 99% of the bacteria then wouldn't this contribute to creating mouthwash resistant bacteria similar to how antibiotics use creates superbugs?

Posted: 12 Mar 2019 04:58 AM PDT

And does this cause any long term concerns when it comes to using mouthwash?

submitted by /u/NicoAtWar
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How does critical mass in an atomic bomb work?

Posted: 12 Mar 2019 06:41 AM PDT

If all the atoms in a small block of Uranium are Uranium-235, what does it matter how much is in there for a chain reaction to occur?

submitted by /u/-james--
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Did humans and fish came from the same biological organism (like the saying "we all come from the sea") or is it possible that life developed independently in the oceans and on land?

Posted: 11 Mar 2019 09:06 PM PDT

P.s.- sorry if I messed up some of the "terms" I'm no expert. 🙈

submitted by /u/sagsag2150
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Magnets stick together one way and repel the other. If you had something that could clamp some big magnets together while they were trying to repel. Overtime is there any reaction?

Posted: 12 Mar 2019 04:25 AM PDT

Are anti-photons a thing?

Posted: 11 Mar 2019 10:26 PM PDT

If so could you have a flash light that emits darkness?

submitted by /u/claytonkevin777
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Does what language you’re raised with change your behaviour?

Posted: 12 Mar 2019 04:46 AM PDT

If you were raised with English, would you have a higher chance of being more aggressive, timid or anything like that? Does a language that could have more words with more aggressive connotations lead to someone with that ingrained in their personality, and if they were to learn a second language, could it bleed into that?

I'm not sure if I've worded my question properly because the though just appeared in my mind.

submitted by /u/Papershredder11
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How will the James Web Space Telescope orbit AROUND L2 lagrange point?

Posted: 11 Mar 2019 08:15 PM PDT

I've been reading up on the James Web Space Telescope and how it will orbit around the L2 point. I'm familiar with lagrange points and the balance of gravity which allows objects to be stable or meta-stable to have the same orbital speed around the sun as the Earth does while being in a different orbit "elevation", but how will the telescope orbit around the L2 point when there's not actually any attractor there?

As I understand it, the L1, L2, and L3 points are the meta-stable ones, akin to a bowling ball being able to sit on top of a very small plateau on top of a peak. Move too far from the L plateau, and the ball will roll down the mountain into the nearest gravity well. The JWST orbiting around the L2 at a distance seems to me like it would be circling the mountain at a constant elevation contour line below the level of the plateau, without ever rolling down hill.

In contrast, the L4 and L5 points, being stable points, would be more like a saddle bowl on the side of the mountain with a small lake in it. The bowling ball could orbit around those lakes in the bowl with centripetal force keeping them at a stable elevation, ignoring friction.

Is it the same phenomenon with the L2 point? Is it actually a lake at the top of the mountain with its own little bowl? I suppose that would look more like a volcanic crater, but I digress. In such a case the ball would be rolling around the rim of the crater, but would not have to stay in the center of a small plateau. But being that case, how would the L2 be meta-stable and any different from the stable L4 and L5?

Can anyone explain or point me to a good source? I've not been able to find anything Googling, but having the right term for the phenomenon might help. Thanks!

submitted by /u/rex8499
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Is it possible for something to reach quadruple point? (Solid, liquid, gas, and plasma)

Posted: 11 Mar 2019 10:14 PM PDT

I seen a video where a liquid was simultaneously changing to solid and gas (called triple point) and made me curious to know if it's possible for it to be plasma also.

submitted by /u/Trixsta397
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Will a beam of sound moving perpendicular to gravity begin to rise, descend, or continue straight?

Posted: 12 Mar 2019 05:40 AM PDT

Can someone explain what Bose-Einstein condensate is? How does it differ from other forms of matter in regards towards physical properties?

Posted: 12 Mar 2019 08:14 AM PDT

I have attempted to research this subject online, but most resources are very vague. Thanks for the help!

submitted by /u/michaelmichael12
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Is it possible to use pacemaker cells for neural stimulation?

Posted: 12 Mar 2019 07:49 AM PDT

I mean maybe pacemaker cells would have to be altered to do the same therapeutic work neural stimulation devices do. But pacemaker cells implanted properly I'd imagine would have less complications and not need battery changes.

I'm just wondering if theoretically pacemaker cells could have medical value after alteration to stimulate that brain and spine for example.

Thanks

submitted by /u/nopasties1
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Approximately how fast is Sol traveling relative to the center of the Milky Way galaxy?

Posted: 11 Mar 2019 04:50 PM PDT

Does the Earth's orbit decay into the sun?

Posted: 11 Mar 2019 11:36 PM PDT

I want to know if the earth would eventually fall into the sun assuming the sun doesn't go super nova on us. Does the earth's orbit decay like satellites and if so by how much and how (if) it affects us.

submitted by /u/Deusbob
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What is the smallest physical size that a flame can be?

Posted: 12 Mar 2019 05:52 AM PDT

How is age of our universe calculated if our solar system was born after the Big Bang? Thanks

Posted: 11 Mar 2019 10:07 PM PDT

How is the age of our universe calculated if our solar system was born after the Big Bang?

submitted by /u/BlackClamSlammer69
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I have heard many times that we can't invent images of human faces so everyone we see in a dream is someone we've seen somewhere in real life. How do we know this?

Posted: 12 Mar 2019 05:21 AM PDT

If Yellowstone decided to finally go supervolcano on us, how much forewarning, if any, would the planet give us? Would it be instantaneous, or would we have days/weeks/months to prepare? What would any such forewarning look like?

Posted: 11 Mar 2019 10:06 AM PDT

What has changed in drug use over the past decades?

Posted: 12 Mar 2019 01:05 AM PDT

As someone who hasn't lived in the 70s and 80s, I often see it portrayed as being an age of parties and drugs.

Is anything known about changes that happened in the drug scene over the past decades (mainly interested in the european scene)? Did drug use increase or decrease? Did drug use stay recreational or did it become more self-medicational? Did the variety used increase or did a lot of kinds of drugs disappear from the streets?

submitted by /u/Amayax
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What is the part of the brain, and how does it function, that allows us to process and repeat units of time (like in a beat)?

Posted: 11 Mar 2019 10:39 PM PDT

Basically the title.

I (and everyone else) can move my hand back and forth, and repeat that motion forever, with the same unit of time elapsing between each movement. That was a really wierd way of describing the motion of a conductor, with the time elapsing between the two peaks of the swing of their arm being the same.

The same can be done by vocalizing, or merely in my head. At first I assumed it had something to do with counting (and it still might idk), but I don't have to assign any unit value (like a second) to it. I can arbitrarily choose a length of time, without even knowing what it would be in seconds, yet I can swing my hand to that exact unit of time over and over again. I can do it for any length, and can alternate it (1 second then 3 seconds then 1 second continuing). Again this can also be spoken or merely thought.

What is the part of the brain that allows me to determine a period of time, recognize it as such, and maintain a repeating pattern where I am aware when each period of that time elapses? I first assumed it had something to do with like a base time, but I can choose or be shown any length of time and can repeat it in my head rhythmically. Where in the brain is this process? How does it work - is there a neuron that holds and releases charge to that period of time, like a circuitboard? How can I identify a unit of time, memorize it, and consistently recognize when it elapses? How does that function?

submitted by /u/EthanMoralesOfficial
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Monday, March 11, 2019

The human population is at 7.7 billion. Has any other mammal ever reached that population level?

The human population is at 7.7 billion. Has any other mammal ever reached that population level?


The human population is at 7.7 billion. Has any other mammal ever reached that population level?

Posted: 10 Mar 2019 01:28 PM PDT

How does your finger "remember" its finger print?

Posted: 11 Mar 2019 01:36 AM PDT

So we all know that a person's fingerprint cannot change naturally. So how does it still produce the same print after the skin is torn? Would the same thing happen if it's burnt?

submitted by /u/Righart
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How do Gyroscopes in electronic devices work?

Posted: 10 Mar 2019 08:33 PM PDT

I've been trying to wrap my mind around how these things work, after playing on a switch for the first time and seeing that the gyro not only detects rotations and flips but also when you turn. So if I sit in a swivel chair and hold the switch in front of me it will detect the full spin of the chair.

I can't wrap my head around how it does this. My first theory was some kind of gyro with a compass to show which way you are facing, but even fast movements are precise, where a compass would wobble a bit.

How exactly are these things detecting full range of motion?

submitted by /u/DocumentaryAndChill
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Why doesn't a pregnant womans immmune system attack the baby?

Posted: 10 Mar 2019 10:10 PM PDT

Why doesn't a pregnant womans immune system attack the baby? Because it is kind of a foreign object in the body since it's different dna?

submitted by /u/wabahoo_on_you
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Why is memory sometimes lost after trauma?

Posted: 11 Mar 2019 01:33 AM PDT

Why is it that in most cases you hear of, it's usually short term or long term memory that is affected or lost after experiencing some kind of head trauma? Why is remembering how to talk or involuntary function rarely affected?

submitted by /u/robbie8six
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Why are Neanderthals classified as a different species from Homo Sapiens?

Posted: 10 Mar 2019 09:53 PM PDT

If they can mate and form viable genetic offspring, what makes them a separate species? Please feel free to apply this same line of logic to all the other separate species that can mate and form viable offspring.

submitted by /u/SketchyFella_
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Are there any known computational systems stronger than a Turing Machine, without the use of oracles (i.e. possible to build in the real world)? If not, do we know definitively whether such a thing is possible or impossible?

Posted: 11 Mar 2019 08:27 AM PDT

For example, a machine that can solve NP-hard problems in P time.

submitted by /u/heyheyhey27
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How are new alloys discovered?

Posted: 11 Mar 2019 01:40 AM PDT

Some alloys have very a long list of very specific amounts of constituents.

For example, Eglin steel is defined as having:
- Iron (84.463–90%)
- Carbon (0.16–0.35%)
- Manganese (0.85%)
- Silicon (max. 1.25%)
- Chromium (max. 1.50–3.25%)
- Molybdenum (max. 0.55%)
- Nickel (5.00%)
- Tungsten (0.70–3.25%)
- Vanadium (0.05–0.3%)
- Copper (0.50%)
- Phosphorus (impurity, max. 0.015%)
- Sulfur (impurity, max. 0.012%)
- Calcium (max. 0.02%)
- Nitrogen (impurity, max. 0.14%)
- Aluminium (max. 0.05%)

How do you end up with these exact quantities of elements? Is it by trial-and-error? Or is there some theoretical basis for mixing the ingredients? Can you predict the material's properties from based on the composition?

submitted by /u/IndependentGuy
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Why is the sky not violet?

Posted: 11 Mar 2019 02:39 AM PDT

Violet has the least wavelength so according to Rayleigh's Law, it would be scattered the most and should be the colour we see the sky as. Why is this not the case?

submitted by /u/notobscurereference
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Is a jellyfish able to sting itself, and if it does what happens?

Posted: 10 Mar 2019 07:23 PM PDT

Rutherford scattering and positively charged nucleus?

Posted: 11 Mar 2019 04:07 AM PDT

Hi all, how did Rutherford arrive at the conclusion that the nucleus of the gold foil was positively charged.

The Rutherford scattering cross section formula is symmetric in charge. Which means both positively and negative charged nucleus could have gave him the same experimental results.

For those skeptical, his 1911 paper only concludes that the small dense nucleus has either a very large positive charge or very large negative charge.

TLDR What evidence helped Rutherford conclude that the nucleus was positively charged?

submitted by /u/StepHawking
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Has any virus or bacteria in humans ever mutated within us to then become a serious illness elsewhere in the animal kingdom?

Posted: 10 Mar 2019 04:50 PM PDT

Why is Hagfish in the subphylum Vertebrata despite having no vertebra/arculia?

Posted: 11 Mar 2019 12:41 AM PDT

During the Fukushima nuclear plant meltdown water was split into hydrogen and oxygen which subsequently exploded. How does this work and how did a supply of gas accumulate without simply burning immediately?

Posted: 10 Mar 2019 06:01 PM PDT

Why does a pot of water or tea pot make the most noise right before the water reaches boiling?

Posted: 10 Mar 2019 04:20 PM PDT

Then it seems to get quieter once it reaches a rolling boil.

submitted by /u/senrnariz
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Do Chloramines in tap water negatively affect human gut microbiome?

Posted: 10 Mar 2019 07:31 PM PDT

Basically the title. I've heard different things about how important the human gut microbiome is to health, and since chlorine and chloramines are typically used to sterilize tap water would it do the same to the human microbiome?

submitted by /u/ramdangeriii
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Does marking a "deep end" of a pool have any effect on rates of drowning or injury?

Posted: 10 Mar 2019 08:26 PM PDT

Most pools I've been to that are deeper than 5 feet delineate between a "shallow end" and the "deep end." The shallow end is normally marked as "no diving," though exceptions are made for swim meets. Is there any evidence that separating the pool into these two sections makes the pool safer to swim in?

submitted by /u/potator
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How did angular momentum come from a singularity?

Posted: 10 Mar 2019 10:20 PM PDT

We know that the early universe was not "homogeneous" because of the cosmic background radiation, but the singularity would have been initially homogeneous by definition. Wouldn't this singularity have to had expanded unevenly for the occurrence of varied forces that cause transnational and rotational motion?

submitted by /u/SleepyHobo
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Does Magnesium and water result in no reaction?

Posted: 10 Mar 2019 08:27 PM PDT

Mg + H2O = NR?

-OR-

Mg + 2 H2O = H2 + Mg(OH)2 ?

I see some sites showing it does result in magnesium hydroxide and hydrogen. But it isn't on the list of metals that react with water. Can anyone clarify this?

submitted by /u/ihugtrees91
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Spacetime isn't like a trapeze net at all is it?

Posted: 10 Mar 2019 09:00 PM PDT

I understand the common descriptives of comparing spacetime to a trapeze net. While it did help at first to wrap my brain around it all, I cannot help but feel like it skips some dimension(s). Is there a better of an exanple anyone knows of that is a bit closer to what spacetime would appear as? 🖖

submitted by /u/Dumble-
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Is it true that you can theoretically make glass out of anything if you cool it fast enough?

Posted: 10 Mar 2019 08:06 PM PDT

I took a class in materials science and the professor said this on multiple occasions, and I believe that I understand it, but I'd like to verify it before it becomes my go-to fun fact.

submitted by /u/UbiquitousSham
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How would orbital bombardment affect the weather?

Posted: 10 Mar 2019 07:43 PM PDT

Trying to write a bit of SF and I'm curious about the meteorological effects of orbitally bombarding an earthlike planet. This comment from AskHistorians about the environmental impacts of WWII is about all the information I have. However, it's concerned with strategic bombing, not orbital bombardment, and it is somewhat vague on the practical consequences of the ionosphere diminishing.

Specifically, I am concerned with bombardment that is somewhat precise (Aimed for selected targets, not indiscriminate glassing) and sustained (More than a week long but less than a month per target area). I have two scenarios in mind: A) The attackers are using a mix of kinetics and conventional explosives for the bombardment B) The attackers are using projectiles that give off very high amounts heat energy, especially upon impact.

Thank you for your help!

submitted by /u/Commissar_Cactus
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How are primers made for PCR chosen?

Posted: 10 Mar 2019 07:02 PM PDT

After DNA has been extracted, how does one know what sequence of nucleotides is complementary to the DNA? PCR is used to increase the amount of a specific part of the DNA so that the DNA can be sequenced, right? How do we know the sequence of that DNA well enough before PCR in order to make a primer for that segment of DNA?

submitted by /u/PebbleSea
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Did humans develop complex vocal chords as an accidental byproduct of evolving to have longer necks or did ancient humans slowly develop them by making enough sounds that more complex vocal chords were forced to be developed?

Posted: 10 Mar 2019 01:36 PM PDT

Did humans just get really lucky to be social animals that accidentally developed complex vocal chords?

submitted by /u/Bathysmal10
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