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Wednesday, September 5, 2018

AskScience AMA Series: I'm Michael Abramoff, a physician/scientist, and Principal Investigator of the study that led the FDA to approve the first ever autonomous diagnostic AI, which makes a clinical decision without a human expert. AMA.

AskScience AMA Series: I'm Michael Abramoff, a physician/scientist, and Principal Investigator of the study that led the FDA to approve the first ever autonomous diagnostic AI, which makes a clinical decision without a human expert. AMA.


AskScience AMA Series: I'm Michael Abramoff, a physician/scientist, and Principal Investigator of the study that led the FDA to approve the first ever autonomous diagnostic AI, which makes a clinical decision without a human expert. AMA.

Posted: 05 Sep 2018 04:17 AM PDT

Nature Digital Medicine published our study last week, and it is open access. This publication had some delay after the FDA approved the AI-system, called IDx-DR, on April 11 of this year.

After the approval, many physicians, scientists, and patients had questions about the safety of the AI system, its design, the design of the clinical trial, the trial results, as well as what the results mean for people with diabetes, for the healthcare system, and the future of AI in healthcare. Now, we are finally able to discuss these questions, and I thought a reddit AMA is the most appropriate place to do so. While this is a true AMA, I want to focus on the paper and the study. Questions about cost, pricing, market strategy, investing, and the like I consider to not be about the science, and are also under the highest regulatory scrutiny, so those will have to wait until a later AMA.

I am a retinal specialist - a physician who specialized in ophthalmology and then did a fellowship in vitreoretinal surgery - who treats patients with retinal diseases and teaches medical students, residents, and fellows. I am also a machine learning and image analysis expert, with a MS in Computer Science focused on Artificial Intelligence, and a PhD in image analysis - Jan Koenderink was one of my advisors. 1989-1990 I was postdoc in Tokyo, Japan, at the RIKEN neural networks research lab. I was one of the original contributors of ImageJ, a widely used open source image analysis app. I have published over 250 peer reviewed journal papers (h-index 53) on AI, image analysis, and retina, am past Editor of the journals IEEE TMI and IOVS, and editor of Nature Scientific Reports, and have 17 patents and 5 patent applications in this area. I am the Watzke Professor of Ophthalmology and Visual Sciences, Electrical and Computer Engineering and Biomedical Engineering at the University of Iowa, and I am proud to say that my former graduate students are successful in AI all over the world. More info on me on my faculty page.

I also am Founder and President of IDx, the company that sponsored the study we will be discussing and that markets the AI system, and thus have a conflict of interest. FDA and other regulatory agencies - depending on where you are located - regulate what I can and cannot say about the AI system performance, and I will indicate when that is the case. More info on the AI system, called labelling, here.

I'll be in and out for a good part of the day, AMA!

submitted by /u/AskScienceModerator
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I read that we look for exoplanets by examining how much they reduce their stars' brightness when they transit. If aliens were observing us, how much would Earth and other planets reduce the sun's brightness?

Posted: 05 Sep 2018 05:31 AM PDT

How far can we possibly see using a telescope (in terms of time and space)?

Posted: 04 Sep 2018 11:34 PM PDT

Question is basically the title plus a little extra. So I've learned in school that if we use a telescope to observe something that's 1 lightyear away, then what we observe is not the thing as it is today but rather how it was 1 year ago. So the farther away the object of observation is, the older the image we observe of it.

 

If this is true, and please correct me if I'm wrong, then given that the universe is 13.8 billion years old and infinitely wide (because it's constantly expanding right?) then what happens if we theoretically try to observe something that's 13.9 billion lightyears away or farther?

 

Since the universe didn't exist before 13.8 billion years ago, there isn't any light that anyone or anything can pick up and observe right? Or is it that we can only possibly see as far as the universe is currently wide, in which case is it really infinite or is it sort of asymptotically infinite? Is it even theoretically possible to build a telescope that could peer across such astronomical distances?

 

And tangentially related this is something that's been on my mind for a while and I'm hoping someone can answer it. Say you teleported to some observatory 200 lightyears away and were able to use a telescope to look back at Earth. Say you could also zoom in enough to see cities. Would you then see the world as it was in the 1800s? Or is this idea itself, barring the obvious outlandish conditions, science fiction?

submitted by /u/skippy130
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Are there any other viable power sources available to us other than electromagnetic induction and photovoltaic technology?

Posted: 05 Sep 2018 05:06 AM PDT

When I make a lost of every source of power generation I can think of, everything comes down to either photovoltaic technology, or spinning a turbine which causes electromagnetic induction. Do we have any other way of powering our homes?

submitted by /u/Capernici
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Why aren’t underwater windmills more of a thing?

Posted: 04 Sep 2018 02:06 PM PDT

The way I reckon it, the tides go through multiple times a day in a predictable way. If turbines just sat there collecting energy 24/7 we'd get a lot of energy. You could put a nearly infinite amount of them up and down the coast line.

submitted by /u/bryan9876543210
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How much more advanced and safer is a nuclear power plant built today compared to one built in 1986?

Posted: 04 Sep 2018 09:10 PM PDT

I was recently thinking about how much better computers have gotten in the past few decades, and wondered if nuclear power plants had improved along the same rate of improvement. I chose 1986 because of the Chernobyl incident, but I'm kind of talking about all types of nuclear power not just the Chernobyl type of reactor. (Also I'm surprised there isn't a Nuclear flair)

submitted by /u/kelloggj
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When a sufficiently sized star dies and collapses into a black hole, does the gravitational attraction that it yields change?

Posted: 04 Sep 2018 10:28 PM PDT

Why do we differentiate between Brønsted–Lowry and Lewis acids/bases?

Posted: 04 Sep 2018 05:04 PM PDT

Which theory is actually used when studying chemistry today? Why is one more useful than the other in different scenarios? The difference between the two theories seems so miniscule to me; why not just stick to one?

submitted by /u/zlibby1998
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How do researchers have so many mice with cancer ?

Posted: 05 Sep 2018 06:49 AM PDT

I mean if X% of mice will have a cancer during their life, do research labs have millions of these waiting for some to get sick or do they have a way to create the cancer in the mouse? (I am not talking about little cigarettes for mice...)

submitted by /u/Owny33x
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Why Don't Lagrange Points Accumulate Matter?

Posted: 04 Sep 2018 12:08 PM PDT

If we can put objects in orbit around them, I would expect natural objects would also find themselves in orbit by chance. What is preventing these points from having natural moons or filling up with debris?

submitted by /u/xonk
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Why is everything trying to reach its lowest energy state?

Posted: 04 Sep 2018 10:19 AM PDT

Does anyone know if the number of blades on a fan has any correlation with airflow or noise?

Posted: 04 Sep 2018 12:48 PM PDT

If the type of element is directly correlated with its number or protons/neutrons/electrons, why aren't there infinite elements and why is 'discovering' a new one a big deal?

Posted: 04 Sep 2018 09:13 AM PDT

Do falling objects radiate gravitons?

Posted: 04 Sep 2018 11:05 AM PDT

If I jump off a cliff, am I sending out gravitons or exchanging gravitons with anything?

submitted by /u/TychoBrastrap
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What semiconductor fabrication method enabled the development of FinFET and other multi-gate transistors?

Posted: 04 Sep 2018 12:04 PM PDT

Hypothetically, would an object in an infinitly large vacuum with a constant force pushing it in one direction accelerate forever?

Posted: 04 Sep 2018 02:34 PM PDT

I have always heard matter can't reach the speed of light, I also know that this hypothetical is essentially impossible because even in the middle of space there are minute forces working on objects, but if you could somehow set this up, where there is no resistance or opposing force acting upon this object, would it ever stop speeding up?

submitted by /u/Mefek
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What properties do the stellar leftovers of very small, low intensity stars (e.g. M and L sequence stars) have after all of their fuel has been consumed?

Posted: 04 Sep 2018 09:52 AM PDT

Could the leftovers be considered "black dwarfs" or is there something else that happens? I'd imagine stars like that would be too small to collapse into black holes or form supernovae.

submitted by /u/rx2893
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Is geostationary orbit possible on Venus?

Posted: 04 Sep 2018 11:29 AM PDT

If ash from erupting volcanos cause rain, why is it that massive forest fires do not?

Posted: 04 Sep 2018 10:47 AM PDT

The understanding I have on volcanos and the atmospheric effects they cause is minimal. I've been told that when volcanos erupt and release ash into the atmosphere, the ash causes rain. However, when we have major forest fires, it seems the ash released by the fire burning doesn't have as big of an impact on causing rain. Is there a difference in the ash produced by a volcano compared to a fire? Or does it still have an effect but just takes longer?

submitted by /u/stormborn1776
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If the universe is flat, how can that be consistent with a big bang origin?

Posted: 05 Sep 2018 01:11 AM PDT

Just ran into an article at RealClearScience.com claiming three problems with the big bang theory. I didn't realize before that the universe is flat as the article claimed. I don't know how a big bang could result in a flat universe.

submitted by /u/TheVarietyChannel
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Tuesday, September 4, 2018

Can we use Moons gravity to generate electricity?

Can we use Moons gravity to generate electricity?


Can we use Moons gravity to generate electricity?

Posted: 04 Sep 2018 06:08 AM PDT

I presume the answer will be no. So I'll turn it into more what-if question:

There was recently news article about a company that stored energy using big blocks of cement which they pulled up to store energy and let fall down to release it again. Lets consider this is a perfect system without any energy losses.

How much would the energy needed and energy restored differ if we took into account position of them Moon? Ie if we pulled the load up when the Moon is right above us and it's gravity 'helps' with the pulling and vice versa when it's on the opposite side of Earth and helps (or atleast doesn't interfere) with the drop.

I know the effect is probably immeasurable so how big the block would need to be (or what other variables would need to change) for a Moon to have any effect? Moon can move oceans afterall.

submitted by /u/noximo
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As the sun burns, is it losing mass, volume, neither or both?

Posted: 04 Sep 2018 06:24 AM PDT

How can humans share 60% of our genes with bananas?

Posted: 03 Sep 2018 08:29 PM PDT

I understand how we can share 96% of our genes with nonhuman primates. And I understand that we share about 99.8-9% of our genes with other people. But how can share 60% of our genes with a banana, which seems to be the same amount we share with fruit flies?

submitted by /u/Quant_Liz_Lemon
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Calculating Earth's convex hull?

Posted: 04 Sep 2018 02:23 AM PDT

I'm curious about Earth's convex hull. That is to say, the minimal polygon that fully encloses the Earth.

Where would the land area with the densest points be? Presumably some plains somewhere, without any mountains on the horizon.

What if we include the ocean floor? Are there enormous plains somewhere there?

Where would the greatest distance between Earth's surface and the convex hull? At the base of some mountain? An ocean trench?

Where is the point on the hull which is furthest removed from any other point (loneliest peak)?

Where is the longest edge (furthest horizon)?

submitted by /u/TheWalruss
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Why is it when sunlight passes through rain, it makes a single (or double) rainbow instead of just a bunch of little teeny rainbows that blend back into white light before reaching the observer?

Posted: 04 Sep 2018 08:24 AM PDT

Why are we immune to some diseases like chickenpox after having it, but not others like strep throat?

Posted: 04 Sep 2018 08:20 AM PDT

Chickenpox is caused by the varicella-zoster virus and once you get it, you can't get it again because your body has produced the antibodies to fight it. Why is this not the case with strep throat which is caused by either a bacteria or a virus? Can you get sick from the same virus more than once?

submitted by /u/spartan6222
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Why copper is used in vacuum insulated travel mugs?

Posted: 04 Sep 2018 01:57 AM PDT

Some of the vacuum travel mug manufacturers plate the inside walls with copper and claim these flasks have better heat retention than regular stainless steel ones. Does it make any sense?

submitted by /u/pavlik_enemy
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How much does the total mass of Earth change?

Posted: 04 Sep 2018 06:19 AM PDT

I'm guessing a lot of the change is in human influences stuff, but how much do we really affect the total mass of the planet? It it even noticeable? Also, does the mass of the Earth increase at all? Does energy from the sun transfer over into mass once it's utilized by organic life?

submitted by /u/charmingtaintman51
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What’s beneath megaliths like Stone Henge and monuments like the pyramids?

Posted: 03 Sep 2018 04:29 PM PDT

I'm not asking how they were erected. There's lots of theories there.

My question is, and I've searched, what kind of base material was used when placing ancient megaliths like Stonehenge? If any?

They don't seem to have moved much, if at all.

Were they placed deep on aggregate material? Were they just stood on the surface? (Surely not!)

The same question applies to menhirs. How are they still securely standing?

I've searched and searched and I can find any real answers. Maybe someone is better at Googling than I...

submitted by /u/412yinz
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Why are children especially vulnerable to measles?

Posted: 03 Sep 2018 11:30 AM PDT

Is it because of a general lack of antibodies, or perhaps because the immune system isn't as well-developed?

submitted by /u/Disappointment123321
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What is the functional difference between fibroblasts and fibrocytes?

Posted: 03 Sep 2018 06:09 PM PDT

Everything I'm reading online says they're different but fails to really explain how. The functions seem really similar (e.g. fibroblasts are characterized by synthesis of proteins of the fibrous matrix, whereas fibrocytes produce connective tissue proteins such as vimentin and collagens I and III) - if they're both synthesizing proteins for connective tissue, in what key ways are they different?

submitted by /u/DoeBites
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How do USB power adapters convert power from outlets to that usable for our phones?

Posted: 03 Sep 2018 02:32 PM PDT

I understand the concept of a transformer which are able to step-up/step-down voltages, but looking into power adapters there are "flyback transformers" and "rectifiers" which confuse me on what they are and the reason for their necessity.

submitted by /u/MightyAccelguard
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How is the tide change in Jupiter, Florida, and Tulum, Mexico only a couple feet, but in South Carolina & other northern places around six to nine feet?

Posted: 03 Sep 2018 06:16 AM PDT

The age of the Earth and Sun is ~4.5B years. Why isn't Earth burned to a cinder by now, if the sun continually emits light?

Posted: 03 Sep 2018 07:47 PM PDT

Earth has been orbiting the Sun for 4.543 billion years (from Google). Apparently the sun has never been turned off in this 4.543 billion years. If so, the sun is continually releasing energy in the form of light. Some of that light is captured by the Earth, heating the Earth. Hence, the Earth has been continually heated for 4.5 billion years. Why isn't Earth almost completely molten right now?

Sorry if this is offensive. I know Earth is NOT molten, and if it was, life would not exist, but I am asking why the Earth is not molten.

submitted by /u/antimatter5
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How do large scale shops/malls supply WiFi on such a big scale?

Posted: 03 Sep 2018 01:47 AM PDT

How do shopping malls and big supermarkets supply a (considering it's size) stable WiFi connection across such a large area? Sent using a shopping centres WiFi with a solid 20mb download.

submitted by /u/Minto00
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What is a calorie?

Posted: 03 Sep 2018 10:31 AM PDT

Carbohydrates and proteins are totally different molecules and used by the body in totally different ways eg proteins are absorbed into muscle and carbohydrates into glucose. So what is being referred to by the term "calorie"?

submitted by /u/solololosolo
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How do we determine whether an animal is self aware?

Posted: 03 Sep 2018 02:13 AM PDT

What is the effect from the use of air conditioning for stopping Climate Change?

Posted: 03 Sep 2018 02:22 PM PDT

Can Climate Change be controlled without sharp reduction in the use of air conditioning?

This article in The Economist projects that we will soon have a billion new a/c units.

submitted by /u/RomanNumeralVI
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Do crows have a season for losing feathers?

Posted: 03 Sep 2018 02:13 AM PDT

I've been seeing crows almost on a daily basis with little to no feathers around the neck area specifically. Do they lose their feathers during different seasons? And why now right before winter when they'll actually be needing feathers to stay warm?

submitted by /u/LolSmokingKills
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Monday, September 3, 2018

When sign language users are medically confused, have dementia, or have mental illnesses, is sign language communication affected in a similar way speech can be? I’m wondering about things like “word salad” or “clanging”.

When sign language users are medically confused, have dementia, or have mental illnesses, is sign language communication affected in a similar way speech can be? I’m wondering about things like “word salad” or “clanging”.


When sign language users are medically confused, have dementia, or have mental illnesses, is sign language communication affected in a similar way speech can be? I’m wondering about things like “word salad” or “clanging”.

Posted: 02 Sep 2018 05:00 PM PDT

Additionally, in hearing people, things like a stroke can effect your ability to communicate ie is there a difference in manifestation of Broca's or Wernicke's aphasia. Is this phenomenon even observed in people who speak with sign language?

Follow up: what is the sign language version of muttering under one's breath? Do sign language users "talk to themselves" with their hands?

submitted by /u/AngrySnowglober
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When an avocado is not ripe, are the fats and nutritional content just as present or does the ripening process make them available? If so, why?

Posted: 02 Sep 2018 07:11 AM PDT

Here I am sitting with a bag full of avocados, and all of them are not quite ripe yet. I wonder if the fat and nutritional content are the same at this stage as when it ripens or if there is a type of transformation that happens as it ripens. If, so, why?

submitted by /u/ginrattle
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Does the ISS need to constantly make micro course corrections to compensate for the crew's activity in cabin to stay in orbit?

Posted: 03 Sep 2018 06:56 AM PDT

I know the crew can't make the ISS plummet to earth by bouncing around, but do they affect its trajectory enough with their day to day business that the station has to account for their movements?

submitted by /u/WunDumGuy
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How do ants breakdown/eat larger insects? Do they eat them on the spot or do they take pieces back to the nest. How does it work?

Posted: 02 Sep 2018 08:17 PM PDT

Is the orbit of Earth around the sun affected by any of the other planets in our solar system? If so, how?

Posted: 02 Sep 2018 07:16 PM PDT

Are there any buildings large enough to be affected by the curvature of the earth? How large would a building of this size be? Also, what engineering methods are used to counteract this?

Posted: 02 Sep 2018 06:03 PM PDT

Why does freezing something make it more “fragile”?

Posted: 03 Sep 2018 06:03 AM PDT

Why are vaccines for things like Ebola are so hard to make?

Posted: 02 Sep 2018 03:55 PM PDT

So my understanding is that vaccines are made from weakend or dead forms of the bacteria or virus responsible for the disease. Why is it so difficult then for vaccines to be made for diseases like Ebola or HIV? What's different about those diseases?

submitted by /u/Vrael22
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What causes the pitch of a sound? Why doesn't the pitch change when it is outside of its tube/voicebox?

Posted: 02 Sep 2018 06:52 PM PDT

Does the curvature of a wineglass affect the frequency?

Posted: 02 Sep 2018 07:06 PM PDT

I am currently writing a report on the 'Singing Glass' experiment. I am measuring the frequency of the noise heard when rubbing your rim around a wineglass using a chromatic tuner while varying the type of wineglass used and the volume of liquid in each wineglass.

Would the curvature of the glass have any affect on the frequency resonated?

submitted by /u/StolenBonBons
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There are many functions that cannot be integrated, ie non elementary integrals. Are there any functions with non elementary derivatives?

Posted: 02 Sep 2018 11:55 PM PDT

Can you measure a particle's position then measure it again after a finite amount of time and find it a distance farther than it could go if it was going the speed of light?

Posted: 02 Sep 2018 03:03 PM PDT

When you measure the position of a particle the wavefunction collapses to the eigenstate of that position in that system. Then it evolves overtime. What is the mechanism of what happens after you measure the particles position that would make it so that it has 0 probability to be found farther than it could go at the speed of light? Is this not a real problem because of how relativistic quantum mechanics works? I was hoping someone would be able to explain the math of how this remains impossible.

submitted by /u/quazzerain
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What exactly was the Debian OpenSSL bug?

Posted: 02 Sep 2018 07:36 PM PDT

There was a famous bug, where in 2008, the Debian maintainers for OpenSSL decided to "fix" a bug where Valgrind was complaining that OpenSSL was copying from an uninitialized buffer. So the maintainer commented out the code, resulting in significantly worse randomness.

But what was OpenSSL doing? Isn't that (assuming that uninitialized variables have old data and aren't 0) undefined behavior, which any compiler could have done behind everyone's back? What was OpenSSL thinking?

submitted by /u/ImMovingFarAwayToStu
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What are we reallly seeing in this gif of a pulsar?

Posted: 02 Sep 2018 07:41 PM PDT

Hello AskScience,

I am making a video game and am trying to visualize some galactic phenomenon and am currently looking at trying to recreate pulsars with particle effects. I found this gif and it looks to me that this is two toruses and a jet. It is hard to tell from this, and I was hoping someone might be able to help clarify what we are really seeing here.

https://media.giphy.com/media/6Iy2GdjElvPUc/giphy.gif

Here is a 3D render of what it looks like to me, but not sure if there are optical effects or I am interepreting this correctly. Any help is appreciated!

https://imgur.com/a/4sLsHzt

submitted by /u/gregdbowen
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Why it is possible to see the interior of a microwave?

Posted: 02 Sep 2018 01:47 PM PDT

As far as my physics and microwave knowledge goes, this machine heats up food using electromagnetic waves, and it uses a Faraday cage to avoid those waves from getting out. But, as light is an electromagnetic wave as well, why those can go through the microwaves's window allowing you to see what's inside, instead of getting blocked?

submitted by /u/Vicara12
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Why do groups alpacas defecate in a communal dung pile?

Posted: 01 Sep 2018 11:07 PM PDT

I've been taught that hydrostatic pressure is calculated with the fromula p = ρgh regardless of the shape of the liquid above. I've seen the proof for it but I still can't get my head around it. Does hydrostatic pressure really work the way the formula says it does?

Posted: 02 Sep 2018 03:44 AM PDT

To explain my confusion, here's a setting that's troubling me:

Let's say that there is a pool whose depth is 1 meter. A scuba diver climbs to that pool and then the pool is sealed with a lid. After this, a 500 meter long straw is poked through the lid and filled with water. Let's say that the straw is very thin and the total amount of water inside the straw weighs 10 grams. Now the scuba diver would experience about the same hydrostatic pressure as if he was 500 meters deep in the ocean, which would kill him without proper equipment. This just does not make any sense to me.

submitted by /u/ComputeralPerson
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What vector space does the elements of gauge groups act on?

Posted: 02 Sep 2018 04:05 AM PDT

On Wikipedia and other places, I can read that the standard model has three gauge groups, U(1), SU(2) and SU(3), for electro, weak and strong forces. These groups are represented by matrices, but nowhere can i find what vector spaces these group elements act on.

submitted by /u/Physix_R_Cool
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Why does turbulent flow cause more erosion than laminar flow?

Posted: 01 Sep 2018 04:37 PM PDT

I'm studying manufacturing processes and while calculating pouring velocity for a molten metal, some books mention that besides the fact that turbulent flow causes splashes while pouring metals in a mold which translates to wasted material, they erode the mold internal surface at a faster rate than pouring it at lower speeds. Why!? Many books mention it, but none explain why. I imagine it to be because the particles bounce around the mold rather than forming an insulation blanket characteristic of laminar flow. But I would like an answer that doesn't originate inside my head. Thanks.

submitted by /u/VaneyRio
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Sunday, September 2, 2018

Does chewing release pleasure neurotransmitters in dogs?

Does chewing release pleasure neurotransmitters in dogs?


Does chewing release pleasure neurotransmitters in dogs?

Posted: 01 Sep 2018 07:53 PM PDT

I'm watching my dog chew on an antler, and he's doing it so intensely and for so long that I assume he must get some sort of benefit out of it. If it does stimulate release of a chemical, which one is it? Dopamine?

submitted by /u/chocolatem00se
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Do dark surfaces contribute to climate change?

Posted: 01 Sep 2018 04:55 PM PDT

Dark surfaces meaning asphalt-paved roads, dark roofs, &c.

submitted by /u/SpenTN
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Does a substance at -1°C and the same substance at 1°C heat up and cool off at the exact same rate when placed into an environment that is 0°C?

Posted: 01 Sep 2018 12:45 PM PDT

Can metals be transparent? If not what quality do substances like glass have that allow them to be transparent?

Posted: 01 Sep 2018 11:36 AM PDT

Is it possible there are naturally occurring, stable, muon based "isotopes" for elements beside hydrogen?

Posted: 01 Sep 2018 07:07 AM PDT

Muonium (an antimuon and an electron) and the theoretical "True Muonium" or Muononium (antimuon and muon) are sometimes considered isotopes of hydrogen, but are both short lived.

Can other muon based elements such as carbon exist, and if so, under what conditions might they occur in the universe?

submitted by /u/Faradizzel
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So does an electron exist as a standing wave, or not?

Posted: 01 Sep 2018 06:27 AM PDT

I'm begun studying quantum mechanics in university and I'm stumped.

In 1923, de Broglie postulated that just like how light can be quantized into photons, and thus act as both a particle and a wave, all matter displays wave-particle duality. Numerous sources online say that de Broglie also proposed that electrons, who would possess wave-like properties thus exist as standing waves, interfering with themselves as they move around the nucleus. As standing waves have specific frequencies for them to form, this would explain how electrons can only exist at discrete energy levels.

My question is : electrons definitely do not exist as standing waves do they? They exist within a cloud of probability density, where their charges are somewhat smudged out, not really in one place. I'm not interested in what an electron looks like or its position, but if electrons are standing waves, then how does that play into the formation of orbitals?

Other sources say that electrons do not exist as standing waves, but are merely a good analogy for how the electron really works. Others state that the standing waves are the results of calculating through Schrodinger's equation, whatever that means. But aren't orbital shapes the result of the equation? Does that mean that orbitals are 3D standing waves?

I've realized that in studying quantum mechanics, lots of times things are said to be facts, then on a deeper level it's more of a "gotcha, it's actually false but I said it was what it was so you could understand THAT, THEN I can say its false when you really dig deeper." I'm doubting whether or not I'm just not all that bright.

Please shed some light on this. Thank you for any clarification given!

submitted by /u/Xeldith
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