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Saturday, December 23, 2017

Are there other problems like random/drunk walk and cross-product which have significantly different solutions depending on the number of dimensions?

Are there other problems like random/drunk walk and cross-product which have significantly different solutions depending on the number of dimensions?

Are there other problems like random/drunk walk and cross-product which have significantly different solutions depending on the number of dimensions?

Posted: 22 Dec 2017 06:38 PM PST

A random walk (drunkard's walk) in one or two dimension will 100%* at some point return to its starting point. In three or more dimensions, a random walk is not guaranteed to return to its starting point.

Another example is the cross product, which is only defined in three and seven dimensions. There is no two-dimensional cross product.

Are there other problems whose solutions (or lack thereof) differ dramatically depending on how many dimensions the problem has?

*100% meaning "almost surely"

C.f. https://en.wikipedia.org/wiki/Random_walk and https://en.wikipedia.org/wiki/Cross_product

submitted by /u/TheNerdyBoy
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How does CRISPR or other gene editing go about overwriting cell information so they know to replicate the new type of cell?

Posted: 22 Dec 2017 06:58 PM PST

I don't know much about cellular biology but I was just reading a post on how they're doing CRISPR trials on lab rats to treat ALS and I started wondering how can they reprogram an entire organisms' cells to know to build themselves differently?

submitted by /u/VirtuallySober
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How do programmers (for hardware) test their code before just... installing it and running it?

Posted: 22 Dec 2017 07:31 PM PST

Why are some vaccinations live virus while some are not?

Posted: 22 Dec 2017 12:30 PM PST

Why are some vaccinations "required" to use the live attenuated virus rather than dead? Is there a biological reason why only some viruses are still effective dead, or do they both work but there is a preference for live virus in some cases?

I know that, for example, immunocompromised patients can not get a live-virus vaccine, which could leave them open to illness. Wouldn't it be better overall to use "dead" virus vaccinations in all cases to get more herd immunity coverage?

submitted by /u/kuuzo
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why are snowflakes flat, instead of 3D?

Posted: 22 Dec 2017 09:36 AM PST

Why is it that, when I leave a crystal lying in the sun for a long time, it loses its color?

Posted: 22 Dec 2017 02:32 PM PST

One time when I was buying some crystals, the person selling them said not to do this, because they'll lose the color, but never actually explained why.

submitted by /u/Meteorite12
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Why does our mouth produce more saliva when we gag or are about to throw up?

Posted: 22 Dec 2017 11:00 AM PST

Austin Eubanks, a Columbine survivor, says "In order to heal [emotional trauma], you have to feel it." Are there scientific studies that back up this assertion? Are there any exceptions to this rule?

Posted: 22 Dec 2017 09:17 AM PST

Austin's statement mirrors conventional wisdom regarding recovery from trauma, but I'd like to dig in further. What's the science on this? Are there scenarios where allowing oneself to experience and confront emotional trauma might be counterproductive?

What about timing? Austin confronted his grief after years of self-medicating his emotions. Could he have recovered sooner if he confronted his grief immediately after the shooting? Or is it possible that trauma victims might need time for grief to subside to a manageable level before confronting it? Can grief subside while one is medicating it? If you can't feel it, can you still heal in some way?

Would appreciate any links to empirical research regarding these questions!

submitted by /u/tacobellscannon
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Can torture victims develop conversion disorder to deal with the pain?

Posted: 22 Dec 2017 06:53 AM PST

Conversion disorder seems to produce psychogenic loss of sensation (various senses) under extreme stress. Why not as a defense mechanism, and can it be done at will for soldiers or a substitute for anesthesia in surgery?

submitted by /u/Flinch123
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Ignoring computer power, is there a maximum limit of the speed of the internet?

Posted: 22 Dec 2017 04:19 AM PST

Like with the fastest computer/router would we have theoretically infinite speeds?

submitted by /u/Pidiotpong
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Does taking antibiotics affect the gut bacteria in any way?

Posted: 22 Dec 2017 08:51 AM PST

As I understand it, taking antibiotics kill or inhibit the growth of bacteria. So, if I take antibiotics then it should also have an effect on my gut bacteria. Is this correct?

submitted by /u/FakeFeynman
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Friday, December 22, 2017

How does the body decide where to store fat?

How does the body decide where to store fat?

How does the body decide where to store fat?

Posted: 22 Dec 2017 05:52 AM PST

In general, females seem to store fat around the hips and thighs, males around the gut. Why? How does the body decide where to store fat?

submitted by /u/Senior0422
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How does a video game or software randomly decide something?

Posted: 21 Dec 2017 09:21 AM PST

I've been wondering this for a long time and has never really found an answer to this.

When a game has a certain percentage chance of getting a critical hit for instance, how does it decide wether or not give you one? I don't quite understand how a computer can just randomly decide something without having a real conscience. It's not like in real life where you can flip a coin or something, it has to have a certain pattern instead, right?

submitted by /u/ArmyAndStuff
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Goldstone is a glassy material with tiny metal crystals suspended in it; copper makes it orange, cobalt blue, chromium green and manganese purple. Are there other metals (gold, silver, titanium) that can be used in this way, and what colour glass do they make?

Posted: 22 Dec 2017 06:14 AM PST

There isn't a huge amount of information on the wiki page (https://en.wikipedia.org/wiki/Goldstone_(glass) ) but basically it's a glass melted with metal oxides and melted in a low-oxygen environment until it becomes a deeply-coloured glass with sparkly little metal crystals suspended within. Invented in Venice because of course it was.

I have some of the standard orange and the blue and I looked up what the 'blue goldstone' was, and found it was made with a different metal - hence the question.

Thank you!

submitted by /u/SongsOfDragons
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Are humans the only animals that view things as 'cute'?

Posted: 22 Dec 2017 05:58 AM PST

I once read in a book, I believe, that infant animals have large pupils in order to have a cuteness factor, so that they are not immediately killed when seen by another animal. Are humans the only animals that perceive this 'cuteness factor'?

submitted by /u/andrewruegsegger
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Is it really better for your hair not to use shampoo?

Posted: 22 Dec 2017 05:45 AM PST

Does insects or animals get bored?

Posted: 21 Dec 2017 07:36 PM PST

I started thinking about how boring it was for a spider sitting on my wall for two days straigth, same spot, not dead (I blew on it, and it reacted). Don't they get "bored" sitting there? Or is it that they are not sentient that removes that ability to feel bored?

What about dogs, cats etc?

submitted by /u/KimJungFu
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How are huge prime numbers with hundreds of digits generated?

Posted: 22 Dec 2017 06:02 AM PST

Like those used in RSA encryption.

submitted by /u/zSilverFox
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Why do most poisonous household products say “Do not induce vomiting?”

Posted: 22 Dec 2017 06:45 AM PST

It seems like if you drink poison you'd want to get it out of your stomach quickly before it gets absorbed. Not inducing vomiting seems counterintuitive.

submitted by /u/sixboogers
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Are there fungi that live completely underwater?

Posted: 21 Dec 2017 07:02 PM PST

What happens to your muscles after you warm up? Why does it result in a reduced chance of injury?

Posted: 21 Dec 2017 09:25 AM PST

What's the highest temperature we reproduced?

Posted: 22 Dec 2017 04:18 AM PST

Be it in a lab or thru a human-made device such as a bomb.

submitted by /u/blues-brother90
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Why are gastrointestinal symptoms associated with the flu only for children?

Posted: 22 Dec 2017 06:03 AM PST

According to Wikipedia, under symptoms of influenza it says "In children, gastrointestinal symptoms such as diarrhea and abdominal pain". It goes on to say "Diarrhea is not normally a symptom of influenza in adults". (The references for these statements appear to be physical texts, so I have not been able to check the sources.)

I can understand that in many illnesses, effects may be worse for children than adults due to less developed immune systems, less exposure to similar conditions, or literally just less body mass to cope with it - but from the wording this appears to be a more fundamental thing.

So why are these symptoms only seen in children? Or have I misunderstood the article?

submitted by /u/cfmdobbie
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How strong were ancient telescopes?

Posted: 22 Dec 2017 06:35 AM PST

Just wondering how strong the telescopes used by the astronomers who first discovered planets were. Like were they the strength of a kids telsescope today from a Walmart or did they have something beefier?

And a side question, are there still areas on earth with night skies as dark as they would have been for the ancient astronomers?

submitted by /u/KingOblepias
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Could the radiation in space be used to peer into the gas giants?

Posted: 22 Dec 2017 06:23 AM PST

If you have a capacitor in parallel with a cell and a resistor, why does the maximum voltage through the resistor before charging never equal the voltage of the capacitor after charging?

Posted: 22 Dec 2017 06:42 AM PST

How Important is handwashing / sterility to the practice of medicine?

Posted: 21 Dec 2017 06:31 PM PST

I recently learned that Doctors didn't understand the need to wash their hands prior to surgery until the 1840's. Wikipedia tells me this is due to a failure to understand how germs are spread.

I have practically no formal medical training (CPR, Heimlich), but I know that you should wash your hands to avoid the spread of disease, and that Chlorine Bleach is good for sanitizing metal tools, and Alcohol is a good disinfectant, and I know that bloodletting doesn't help. Would that make me the best doctor of 1839? Would I be easily outclassed by medical professionals, despite their unwashed cadaver dissecting hands?

So much of... pop culture emphasize the mistakes / foolishness of the past. How advanced was a trained doctor of the 1830's? Was cleanliness, and an understanding of how diseases transfer a major threshold for the field of medicine, or just an incremental advancement?

submitted by /u/tag8833
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Where do bees go during colony collapse?

Posted: 21 Dec 2017 07:21 PM PST

Recently I've been reading about Colony Collapse Disorder and how, contrary to my previous assumptions, it's not just bees dropping dead in the hive, but seemingly just disappearing or abandoning it without going through the ordinary procedure. Are these adult bees just wandering around aimlessly until they die? Going about their daily duties but getting lost? Do we even know or have any hypothesis or is it a total mystery?

submitted by /u/TheWormInWaiting
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What is the actual reason why noble gases are chemically inert?

Posted: 22 Dec 2017 05:54 AM PST

I know that the standard reason in textbooks is that their valence shells are full, but why should that in turn cause them to be chemically inert? What is it about full valence shells that causes atoms to be inert?

I guess another way of asking the same question would be: what is the deeper reason for the octet rule in Chemistry?

submitted by /u/krantibum
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How small does a celestial object need to be in order to be shaped into a sphere by it's own gravity? [Astronomy - Planetary Formation]

Posted: 21 Dec 2017 05:30 PM PST

Maybe I'm not asking this question correctly.. just popped in my head and was curious so here I am, r/askscience!

submitted by /u/shredthesweetpow
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What's wrong with this argument of going faster than speed of light?

Posted: 22 Dec 2017 03:29 AM PST

I read somewhere, that say, if I point a laser at the northern most part of Jupiter here from Earth, and then in less than a millisecond, I twist my wirst so that the laser now is at southern most point, the laser would have travelled a very large distance, and with some calculations, we can show that the speed of the tip of laser was greater than that of light.

Now, I know breaking the barrier isn't possible, but could anyone please explain to me what wrong is it that I'm doing here... :)

submitted by /u/carbon_c60
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Would stirring water really fast make it warmer?

Posted: 21 Dec 2017 08:12 AM PST

If I were able to stir water extremely fast, would it be possible to bring it to a boiling point?

submitted by /u/DiogenicOrder
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Many businesses under the new US tax plan stated they will not be allocating more money into capital investments. Instead, many will be issuing stock buybacks and dividend increases. What, from an economic perspective, drives this decision?

Posted: 21 Dec 2017 07:11 AM PST

Can a material under high stress break at random without any additional change to the system?

Posted: 21 Dec 2017 01:06 PM PST

Lets say a ballpoint pen is pushing on the centre of a tensioned sheet of foil so that the foil is as close to its breaking point as possible. If there are no external changes (vibrations, temperature change, etc.) could the foil still randomly snap?

This was just an analogy similar to the situation that had me puzzling, but apply it to the breaking point of any material if preferable.

submitted by /u/Stimulated_Bacon
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Thursday, December 21, 2017

How much bandwidth does the spinal cord have?

How much bandwidth does the spinal cord have?

How much bandwidth does the spinal cord have?

Posted: 20 Dec 2017 03:01 PM PST

I was having an EMG test today and started talking with the neurologist about nerves and their capacity to transmit signals. I asked him what a nerve's rest period was before it can signal again, and if a nerve can handle more than one signal simultaneously. He told me that most nerves can handle many signals in both directions each way, depending on how many were bundled together.

This got me thinking, given some rough parameters on the speed of signal and how many times the nerve can fire in a second, can the bandwidth of the spinal cord be calculated and expressed as Mb/s?

submitted by /u/jorshrod
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How does the circulatory system adjust to the greater volume of bodymass in obese people?

Posted: 20 Dec 2017 06:44 PM PST

What would happen if your brain floated in water instead of cerebrospinal fluid?

Posted: 20 Dec 2017 06:27 PM PST

I think it's safe to say we wouldn't be able to function as humans, since the CFS apparently provides some pretty vital functions like protecting the brain against blood pressure spikes. That's the extent of what I know though, so can anyone tell me exactly what would happen if all the CFS in our skulls were suddenly replaced with pure, distilled water?

submitted by /u/Neil5555
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If you put a live power cable in the sea, how far away could it electrocute someone?

Posted: 20 Dec 2017 12:36 PM PST

What got me thinking about this in general was wondering about my house flooding and whether or not the electricity box becoming compromised with water could cause all of the water to become electrified.

Also, I remember a scene from Ozark, the Netflix show starring Jason Bateman, where something similar to my original question happened in a large body of water.

submitted by /u/Aedum1
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Can sea creatures be invasive?

Posted: 20 Dec 2017 07:38 PM PST

As we all probably know there are many instances of animals being introduced to a new environment and having no natural predators and become a problem. I know this can also happen with fish too in lakes and rivers. My question is can this happen in the ocean since one way or another all the ocean is connected.

submitted by /u/purplechickenfish
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Why Does The LHC Reach Such High Temperatures?

Posted: 20 Dec 2017 06:42 PM PST

I saw on reddit that one of the highest temperatures we know of in the universe was created at the LHC. I don't know a ton about the LHC other than it smashes particles together, but wanted to ask what causes it to reach such high temperatures?

I think I read somewhere that some of the experiments turn matter into energy, is that what causes it?

Thanks!

submitted by /u/notalltogetherhere
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Other than Neanderthals, did humans live alongside any other homo species?

Posted: 20 Dec 2017 04:30 PM PST

Why do some medicine need to be taken on a full stomach/with food where as for others it doesn't make a difference??

Posted: 20 Dec 2017 11:58 AM PST

Can drinking alcohol prevent food poisoning?

Posted: 20 Dec 2017 03:31 PM PST

Alcohol can be used as disinfectant, so if you had some food that was just starting to go bad, or perhaps had some mold or was past it's expiration date, would drinking liquor with the meal kill the bacteria that makes you sick? What about wine or beer? Is there a certain proof needed to kill bacteria, and does it only affect certain types of food related illness?

submitted by /u/Afireonthesnow
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What specific animals are affected by the cicadas' life cycle?

Posted: 20 Dec 2017 03:56 PM PST

Does anyone know any specific species that are affected by the cicadas' 13 or 17 year cycle?

submitted by /u/DwarfOfTheNwarf
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Theoretically, is it possible to create an atom big enough with enough protons, neutrons, and electrons to be observable with the naked human eye?

Posted: 20 Dec 2017 11:29 AM PST

Even if it was for a fraction of second, is it feasibly possible? Or is there a limit to how big an atom can be?

submitted by /u/Miesterman
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What causes LA (local anesthetic) resistance?

Posted: 20 Dec 2017 09:36 AM PST

One of my molars needed a cavity filled, so the dentist did the typical cotton swab followed by injection of Lidocaine. 5 minutes later, he came back and tried to drill into it. Know that pain you get when you have a cavity and bite in to either something very cold or very sugary? It was like that, but 10x. He gave me another shot of Lidocaine and tried again 5 minutes later. The same pain, if a little bit less. He had to do a nerve block shot, and even then I could feel it a little bit. Did a bit of reading about anesthetic resistance and apparently this subject has not been extensively researched.

Does anyone else here have experience with this or has studied it? Apparently it's only a very small amount of population that has this resistance, I'm just glad that I'm not completely resistant. How does it work and why has it not been thoroughly studied?

submitted by /u/wulfgar_beornegar
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In epidemiology, how do we determine the r₀ value of a new disease?

Posted: 20 Dec 2017 11:42 AM PST

Does milk spoil inside of female mammals?

Posted: 20 Dec 2017 09:52 AM PST

If a female, let's say cow, isn't milked for a while, does her milk spoil in the same way milk spoils if left out in a similarly temperatured container?

submitted by /u/jbhelms
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Is there such a thing as geometrical body that has the MAXIMUM area for a given volume?

Posted: 20 Dec 2017 07:31 AM PST

In 3D space, a sphere is the geometrical body that has the minimum area for a given volume. Is there such a thing as an...uh..anti-sphere?

submitted by /u/Iazo
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How does our brains look for stored information?

Posted: 20 Dec 2017 10:54 AM PST

So I saw a picture of Tom Cruise and wanted to google him. But I couldn't remember his name, I knew that I know what's his name is but at the moment it didn't come to me. Nicolas Cage, no, Brad Pitt, none of them fit. Then I thought; he's a scientologist which made me think of Jon Travolta but thats the other guy.. Suddenly I remembered southpark and the word closet and then the quote "Tom Cruise wont come out of the closet" and boom I had his name. But how does this all work?

submitted by /u/spirates
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What is the effect of planetary radius and mass on atmospheric depth and density and flight?

Posted: 20 Dec 2017 02:16 PM PST

What is the effect on the size and density of the atmosphere and its effect on flight? Planet mass is 1.030843538230884704452608 × 1025 kg and the size is 8.292 * 106 km.

submitted by /u/MrJadexxxxxxx
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Is intelligence based on your genetics? If so, how does that work?

Posted: 20 Dec 2017 08:34 AM PST

What makes whole genome sequencing so difficult?

Posted: 20 Dec 2017 07:50 AM PST

Recently I've been reading into the topic, and discovered the human genome has never been completely sequenced.

I understand that parts of the genome that are very repetitive are harder to piece back together, but why is it difficult to read long chunks at a time?

Thanks!

P.S. If you know of any books or other resources on the modern challenges to whole genome sequencing, please point me in the right direction!

submitted by /u/bwbonanno
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