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Friday, January 29, 2021

Is contagious yawning a cultural/learned thing or is it hardwired into us?

Is contagious yawning a cultural/learned thing or is it hardwired into us?

Is contagious yawning a cultural/learned thing or is it hardwired into us?

Posted: 28 Jan 2021 10:14 PM PST

When I see someone else yawn it's almost automatic that I will yawn. Even just writing this made me yawn.

But I've noticed that my young children don't do this.

So is my instinct to yawn because there is some innate connection in human brains or is this something I do because grew up around would do it and I learned it from them?

Maybe another way to ask this would be are there cultures that don't have this? (I've seen pop psychology stuff taking about psychopaths and sociopaths but doing it. That's not what I'm referring to, I mean a large majority of a group not doing it)

submitted by /u/AlbinoBeefalo
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Are there flying arthropods that aren't insects?

Posted: 28 Jan 2021 08:59 PM PST

Would the USA accept European approvals for Novavax (and other vaccines), or does it still require US trials?

Posted: 29 Jan 2021 05:15 AM PST

Are there scientific differences in how EU vs US trials are performed?

Does the FDA allow this in exceptional times (like the current pandemic?)

submitted by /u/crimson117
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Can heavy rain cause the sea level to rise temporarily in that area?

Posted: 28 Jan 2021 07:54 PM PST

What is the fate of lipid nanoparticles in certain COVID-19 vaccines?

Posted: 29 Jan 2021 05:24 AM PST

Relatively little attention seems to be given to the lipid nanoparticle formulations when discussing the safety and efficacy of the new mRNA vaccines.

It would seem the lipid nanoparticles are needed to make an efficacious vaccine, but what do we know about the short and long-term fate of these lipid nanoparticles inside the human body?

submitted by /u/a_sesquipedalian
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What is the difference between Pathology, Pathogenicity and Pathogenesis of a virus?

Posted: 29 Jan 2021 03:50 AM PST

Why did Earth's rotational velocity recently increase?

Posted: 28 Jan 2021 07:47 PM PST

I keep reading that we're thinking of taking away the "Leap Second" this year because Earth's velocity increased in 2020, but I'm seeing little explanation for why that might occur. Some super large rock formation moving around in the lower mantle? Some weird phenomenon in the core? What are the most plausible explanations?

submitted by /u/HybridVigor
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Are the new Coronavirus strains popping up meaningfully different from the original variant that saw mass infection?

Posted: 28 Jan 2021 06:34 PM PST

Afaik it's commonly accepted in the scientific community that over time pathogens typically become more and more mild. The idea being that you want to still infect your host, as that is essential for survival, but the more you disrupt their ability to survive the less likely you are able to spread and thus survive yourself. In humans there is also the added pressure to evolve this way because we actively combat severe pathogens but don't to nearly the same extent with the more mild ones. A good example of this effect would be something like a common cold.

Beyond just being physically different from their ancestor, how are the new strains popping up around the world different? Are they less/more lethal? Less/more infectious? Cause more/less long-term damage?

I'm quite curious to see if the phenomenon I described is occuring within the COVID-19 virus, essentially, and if this rule-of-thumb in Pathology is observable in this specific instance.

submitted by /u/Mdrogun
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At the beginning of the vaccin trials it was said that the change for those trials to fail was very large, did any of those trials actually fail, and how much did so?

Posted: 29 Jan 2021 02:03 AM PST

At the start of the vaccin trails I read many times on reddit that the chance for the trials to fail is larger than success. But since then I haven't heard of any failed trials and cancelled vaccin research. Were there any vaccine researches that were cancelled? And how is it possible that the most talked about vaccin researches all succeeded? Were the numbers people gave at the beginning regarding the chance of such trials to fail false?

(Sorry for bad formulation, English is not my first language)

submitted by /u/Sophie_333
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Why do photons get absorbed and quickly expelled in the radiation zone but get absorbed and held in the convection zone?

Posted: 28 Jan 2021 07:24 PM PST

I am talking about stars here. Photons are generated in the core and then get emitted and then get absorbed and expelled by nuclei and protons in the radiation zone, however once it reaches the convection zone then it gets absorbed and the energy stays with the particle until it hits the surface.

I am wondering why this happens.

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Are carbon dating methods reliable?

Posted: 28 Jan 2021 07:42 PM PST

Hello everyone. I'm new to this subreddit, but I have a question. Is carbon dating reliable? I have heard many rebuttals from young earthers who claim things such as: *water (a flood) tampers with carbon dating methods *rocks where we know the age (i.e formed in an eruption or lab made) date millions of years old *carbon levels were not always the same I am not a scientist, so this video has me stumped. Any and all answers are appreciated. Thanks!

https://youtu.be/fg6MfnmxPB4

submitted by /u/klauver
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Why do viruses make you sick ?

Posted: 28 Jan 2021 09:33 AM PST

The only goal of a virus is to multiply. Making you sick does not help that goal. Killing the host will kill all the virus in it also. So why have most viruses not evolved to harmlessly enter their hosts?

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What is the relationship between vomiting and brain injuries?

Posted: 28 Jan 2021 08:45 PM PST

Traumatic brain injuries have vomiting as one of their possible symptoms. What is it about brain injuries that trigger vomiting?

submitted by /u/Benjips
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Why do ion thrusters produce so little thrust?

Posted: 28 Jan 2021 08:51 PM PST

What law of physics forbid it from having higher thrust?

submitted by /u/Gabriel38
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How is a magnetar formed compared to a neutron star?

Posted: 28 Jan 2021 01:26 AM PST

So I think understand that a magnetar is a form of neutron star and both are created by the collapse of a larger type of star, but what causes one to be a magnetar specifically? Is it related to the entropy of that specific star car similar to what I was reading in a previous post? Or is there something I'm completely misunderstanding?

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Thursday, January 28, 2021

What does "Entropy" mean?

What does "Entropy" mean?

What does "Entropy" mean?

Posted: 27 Jan 2021 02:20 PM PST

so i know it has to do with the second law of thermodynamics, which as far as i know means that different kinds of energy will always try to "spread themselves out", unless hindered. but what exactly does 'entropy' mean. what does it like define or where does it fit in.

submitted by /u/bert_the_destroyer
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AskScience AMA Series: I am Avi Loeb and I'm here to explain how I noticed the first tentative sign for Intelligent life beyond earth. AMA!

Posted: 28 Jan 2021 06:12 AM PST

I am the Frank B. Baird, Jr., Professor of Science at Harvard University. I received a PhD in Physics from the Hebrew University of Jerusalem in Israel at age 24, while leading the first international project supported by the Strategic Defense Initiative (1983-1988). Subsequently I was a long-term member of the Institute for Advanced Study at Princeton (1988-1993). Throughout my career, I have written 8 books, including most recently, Extraterrestrial (Houghton Mifflin Harcourt, 2021), and about 800 papers (with an h-index of 112) on a wide range of topics, including black holes, the first stars, the search for extraterrestrial life and the future of the Universe. I had been the longest serving Chair of Harvard's Department of Astronomy (2011- 2020), Founding Director of Harvard's Black Hole Initiative (2016-present) and Director of the Institute for Theory and Computation (2007-present) within the Harvard-Smithsonian Center for Astrophysics. I also chair the Board on Physics and Astronomy of the National Academies (2018-present) which oversees all Decadal Surveys in Physics and Astronomy. I am an elected fellow of the American Academy of Arts & Sciences, the American Physical Society, and the International Academy of Astronautics. In addition, I am a member of the President's Council of Advisors on Science and Technology (PCAST) at the White House and a member of the Advisory Board for "Einstein: Visualize the Impossible" of the Hebrew University. I also chairs the Advisory Committee for the Breakthrough Starshot Initiative (2016-present) and serve as the Science Theory Director for all Initiatives of the Breakthrough Prize Foundation. In 2012, TIME magazine [pdf] selected me as one of the 25 most influential people in space and in 2020 I was selected among the 14 most inspiring Israelis of the last decade. Click here for my commentaries on innovation and diversity.

I will be on at 11a.m. EST (16 UT), AMA!

Username: /u/Avi-Loeb

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When astronomers refer to distances between galaxies, do they mean the distance as we observe them or as they are now?

Posted: 27 Jan 2021 11:20 PM PST

For example, if astronomers describe the distance between two galaxies in a supervoid that is a billion light-years away to be 150 million light-years. Is that distance representative of what we have observed (essentially an image from a billion years ago) or as it is now (accounting for the expansion of the universe)?

submitted by /u/stuffdude99
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Do older people vaccinated for Covid have a “good” immune response from it?

Posted: 28 Jan 2021 05:18 AM PST

My otherwise very healthy and independent 94yo grandmother received her first Covid vaccine 5 days ago. I asked her if her arm was as sore as mine and she said it doesn't hurt at all. I was wondering if the immune response in the older population has been studied much. I'm just curious if her complete lack of side effects is an indication that her body did not get a strong immune response.

submitted by /u/BRCRN
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If all electrons are identical, then how can they have different energy levels?

Posted: 28 Jan 2021 06:33 AM PST

I've heard that the farther an electron is from the nucleus, the more energetic it is. But how can this be if all electrons are identical?

submitted by /u/imgoingdef
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Do gravitional waves effect time?

Posted: 27 Jan 2021 09:47 PM PST

Since gravitional waves are ripples in space-time, how do they effect the time component? Is there any kind of time dilation?

submitted by /u/RigbyAtNight
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How does an increase in humidity assist plant growth?

Posted: 27 Jan 2021 11:14 PM PST

For many indoor plants that have evolved to live in more humid environments, it appears that reducing humidity levels can impair their growth. Why is this? Given that an increase in humidity decreases the rate of transpiration and thus slows nutrient uptake from the soil, why would they grow faster?

submitted by /u/Fartfenoogin
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How laser measuring tools work?

Posted: 27 Jan 2021 07:23 PM PST

Ultrasound space measuring works by measuring the time it takes to a sound wave go, reflect and return to the tool. But we cant really measure the speed of light cuz it is too fast to be detected, so laser measuring tools can't work like ultrasound tools. So how does it work?

submitted by /u/MCarooney
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Do all vaccines get tested for sterilising immunity?

Posted: 27 Jan 2021 03:11 PM PST

People are saying that we don't know if the new COVID vaccines will affect transmission of COVID. Every other vaccine I heard of stops transmission of whatever they're vaccinating against, so I don't understand why this would be different. However, if they all need to be tested for this I would understand, as it would then just be a routine question. Do all vaccines need to be specifically evaluated for sterilising immunity, or is this something we're only worried about with the new vaccines?

submitted by /u/namedbymybrother
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With sunglasses on, one of my computer monitors is almost unaffected, only slightly darker, and the other one turns entirely black. What about monitors or sunglasses makes them react differently?

Posted: 27 Jan 2021 02:30 PM PST

Optics/Eye anatomy: How *exactly* does the eye perceive the color green from a mixture of yellow and cyan pigments on a white sheet of paper?

Posted: 27 Jan 2021 02:18 PM PST

Thanks in advance for entertaining my very basic question. Here's what I think I know so far:

White light shines from a light source and hits the cyan and yellow pigments. The pigments reflect the wavelengths that correspond to cyan (ca 475nm) and yellow (ca 580nm) respectively, and absorb the rest. The "cyan" and "yellow" wavelengths then enter the eye.

If the above is correct, does that mean that the tristimulus values of spectral green and cyan+yellow are the same, like in the case of yellow and green+red?

Apologies if this is a dumb question. I think my confusion comes in part from trying to figure how additive and subtractive color models fit in the real world. Would it be accurate to say that subtractive color is a part of physical reality, while additive color exists only as a part of human perception?

Bonus question: I understand that in reality a blue object does reflect other wavelengths besides "blue" ones, albeit at a lower intensity. But are there chemicals or chemical structures that manage to exclusively reflect an incredibly narrow range of wavelengths (say, 500-505nm), without reflecting any other wavelengths at any degree of intensity?

Thank you for your time!

submitted by /u/Grain_in_a_Jar
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Why do infected cases grow in waves during a pandemic?

Posted: 27 Jan 2021 11:04 AM PST

At the beginning of the coronavirus pandemic they kept telling us on the news about how it would come in waves, and from looking at regional charts, it really has happened in waves.

Is that because of human behavior or something to do with the virus itself or what?

Edit: to clarify my question, if we didn't do lockdowns, didn't have holidays, or other human type of social behavior changes, would we still see the disease spread in waves?

submitted by /u/mntgoat
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What causes the steams different behaviour?

Posted: 27 Jan 2021 11:02 PM PST

Why is it that the steam coming from outside into my bathroom, through my window, is falling to the floor, whilst the steam coming from inside the shower cubicle rises to the ceiling?

PS: I'm not sure which category this is, but I believe it's physics

submitted by /u/Kasper_II
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Are the current COVID-19 vaccines not as effective for certain races?

Posted: 27 Jan 2021 04:45 PM PST

I just read an article from MIT that said the immune response was not as strong in people with certain genetic backgrounds (they specifically mentioned Asians).

I don't understand the science behind the research. Is this a concern? If so, can the drug manufacturers improve the vaccines?

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Is it possible to store video data as a photo?

Posted: 27 Jan 2021 09:45 PM PST

This probably sounds like a dumb pointless question and I'm sorry if this isn't the right sub to be asking this sort of thing. I know there are ways of making sounds into images and vice versa, like using SSTV image generators and decoders for example. I was wondering if there is a way you can take the digital video data from a video and save it or transform it into a single picture? Hopefully this makes sense.

submitted by /u/Awkwarddruid
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I'm watching Fritz Lang's 1931 silent film "Woman in the Moon" and they got surprisingly accurate with some of the science of orbital mechanics. When (and who) calculated the physics of spaceflight to the moon?

Posted: 27 Jan 2021 01:28 AM PST

Outside the whole "we can breathe on the moon" aspect, the 1931 silent film surprised me with the accuracy of the spaceflight facts a decade or two before the big rocket programs:

  • "we will land 36 hours later on the far side of the moon"
  • "necessary speed of 11,200 meters per second" (escape velocity)
  • The need to cut the rocket motors or speed past the moon.
  • 8 minutes of acceleration, then at 227,00km above Earth, coasting, and weightlessness.

Kepler and Newton advanced planetary mechanics and Halley famously applied that to his comet, but I can't seem to find info on the first to figure out spaceflight parameters for a flight to the moon. (Probably just flubbing search terms late at night.)

submitted by /u/westtxfun
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Wednesday, January 27, 2021

I keep reading about how Covid has had a worse effect on minorities in the US particularly blacks. Is this all because of environmental/societal reasons, or do people of African decent actually have a harder time with the virus physically?

I keep reading about how Covid has had a worse effect on minorities in the US particularly blacks. Is this all because of environmental/societal reasons, or do people of African decent actually have a harder time with the virus physically?

I keep reading about how Covid has had a worse effect on minorities in the US particularly blacks. Is this all because of environmental/societal reasons, or do people of African decent actually have a harder time with the virus physically?

Posted: 27 Jan 2021 05:33 AM PST

do your teeth move at night?

Posted: 27 Jan 2021 03:09 AM PST

ik this sounds weird lol but i think i remember someone saying/reading somewhere that your body swells a little bit while you sleep. but when i stay up way extra too late it feels like when i bite down my teeth aren't in the right place.. if that makes sense, just slightly shifted. so are your teeth included in this? or your skeleton i guess

submitted by /u/lakendra758
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How do they make COVID-19 mRNA?

Posted: 27 Jan 2021 07:10 AM PST

I've learned that mRNA is essentially a direct order for your cells to make COVID-19 antigens, so instead of your cells taking mRNA from the nucleus, the COVID-19 vaccine mRNA hijacks the mechanism to make COVID-19 antigens.

Now I'm curious how do they actually make such mRNA? Do they snip the genetic material from the virus itself? Or do they have to actually create one?

Sorry if this has been asked before, a link to the thread would be appreciated. Thank you!

submitted by /u/paulaldo
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What causes the boundary layer to separate?

Posted: 27 Jan 2021 02:37 AM PST

I was looking at a example of a fluid flowing past a sphere, it was mentioned that at low velocities the air hugs the ball evenly everywhere, low speed means that less impulse is given to the fluid, therefore the effects of pressure will be much stronger and the back of the ball will suck in the airflow and even out the pressure on the back and front, is this correct?

Then I looked at examples of flow around a ball but a much faster one, then the thing with the boundary layer separating confuses me a lot, i think the cause is the side inertia (can i even call it that, i know its some kind of side force gained from moving in a not straight direction around the ball, it looks like inertia to me) can fight the ow pressure on the back for a time, is this correct it makes sense to me but i cant find any way to confirm it.

submitted by /u/nekoi_si_tam
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Ask Anything Wednesday - Economics, Political Science, Linguistics, Anthropology

Posted: 27 Jan 2021 07:00 AM PST

Welcome to our weekly feature, Ask Anything Wednesday - this week we are focusing on Economics, Political Science, Linguistics, Anthropology

Do you have a question within these topics you weren't sure was worth submitting? Is something a bit too speculative for a typical /r/AskScience post? No question is too big or small for AAW. In this thread you can ask any science-related question! Things like: "What would happen if...", "How will the future...", "If all the rules for 'X' were different...", "Why does my...".

Asking Questions:

Please post your question as a top-level response to this, and our team of panellists will be here to answer and discuss your questions. The other topic areas will appear in future Ask Anything Wednesdays, so if you have other questions not covered by this weeks theme please either hold on to it until those topics come around, or go and post over in our sister subreddit /r/AskScienceDiscussion , where every day is Ask Anything Wednesday! Off-theme questions in this post will be removed to try and keep the thread a manageable size for both our readers and panellists.

Answering Questions:

Please only answer a posted question if you are an expert in the field. The full guidelines for posting responses in AskScience can be found here. In short, this is a moderated subreddit, and responses which do not meet our quality guidelines will be removed. Remember, peer reviewed sources are always appreciated, and anecdotes are absolutely not appropriate. In general if your answer begins with 'I think', or 'I've heard', then it's not suitable for /r/AskScience.

If you would like to become a member of the AskScience panel, please refer to the information provided here.

Past AskAnythingWednesday posts can be found here. Ask away!

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What’s the reasoning for different needle lengths with vaccines?

Posted: 26 Jan 2021 11:24 PM PST

While I do have a background in clinical laboratory science, I'm more versed in the "how it works" from an immunological standpoint and not the "how to deliver it." I understand gauge (we were taught this as it applies to hemolysis, lol), but I'm curious about lengths.

I noticed that my Covid vaccine (Pfizer) needle was quite long today, longer than my flu vaccine. I didn't realize the first time, but for some reason I really wanted to take a look today!

Is this to do with viscosity? I did "feel" the first dose, and my second dose today really did feel like syrup in my arm.

Either way, I'm glad to be vaccinated, I'd love to learn more about this.

submitted by /u/hyphaeheroine
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Does the percentage of vaccinated per capita include children and others that medically or legally can't vaccinate?

Posted: 27 Jan 2021 06:20 AM PST

And if so, why? It's very confusing.

submitted by /u/Yuval8356
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Is there any particular reason that Pangea broke apart parallel to the Appalachian Mountains? If and when Asia and India separate again, are they more likely to do so along the original convergent boundary?

Posted: 26 Jan 2021 06:24 PM PST

How do antibodies fight viruses and bacteria, and what are the differences in dealing with the two? How do they 'know' what to attack? And for a local infection (like from a cut), does the body know to send extra antibodies there, or are they always equally dispersed through the body?

Posted: 27 Jan 2021 07:43 AM PST

Why are there so many Coronavirus variants all of a sudden?

Posted: 27 Jan 2021 06:22 AM PST

I understand that the virus can evolve and mutate, but why is it that after a year of pandemic with no significant mutations, suddenly there are 3 new variants in a few weeks?

Thanks a lot and sorry for English mistakes.

submitted by /u/ChenTasker
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Why are some masks effective against the "normal" covid but not good enough for some of the variants?

Posted: 27 Jan 2021 06:19 AM PST

A lot of people are buying different masks because of the new variants, why don't the masks work if the virus structure/size is basically the same?

submitted by /u/Chora123
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Why are people with Down syndrome more susceptible to covid?

Posted: 26 Jan 2021 02:27 PM PST

I was scrolling Twitter and saw this tweet and became curious. The tweet essentially claims that people with Down syndrome face "risks 10x greater with covid" I did a quick google and found this site that states people with Down syndrome are more likely to have sleep apnea which can add to the risks with covid. Apologies if I haven't thoroughly checked my own source but I can't readily find any more info.

My main question is why are people with Down syndrome so much more at-risk than others, and if it really is all about sleep apnea then why isn't that being discussed more considering many more people suffer from sleep apnea (I believe that is very common with overweight folks, shout-out USA) than Down syndrome to the best of my knowledge.

submitted by /u/JoshRichardson4MVP
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Why do we say electrons in a metal move around with velocities determined by kT instead of the Fermi level?

Posted: 26 Jan 2021 09:42 AM PST

It's all over solid state text books that the velocity of electrons in a metal (assume no applied field) is something like root(kT/m) (I don't care about the 2's and/or 3's that I'm missing). This perspective makes sense because it's sort of the amount of energy an electron might get from the thermal bath it's sitting in.

But also, from QM, if we keep adding fermions (electrons in this case) to the metal, they'll occupy higher and higher energy states. Even at T = 0, the electrons will have nonzero energy, in particular, electrons at the top will be at the Fermi energy. In this case, the thermal velocity would be zero, but the Fermi velocity can get up near a percent of the speed of light (graphene for example). Clearly this is a huge discrepancy.

So, why do we say electron speed is governed by kT instead of the Fermi level?

It's a quantum vs classical issue as pointed out. Dense systems of electrons should go by Fermi energy, sparse systems can use kT.

submitted by /u/rice_jabroni
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In terms of the vaccines, what’s the difference between JNJ-78436735 and Ad26.COV2.S? How many types of vaccines is Johnson & Johnson developing, and which one is planned to roll out soon?

Posted: 26 Jan 2021 06:58 PM PST

Maybe I'm misunderstanding this, but can someone clearly delineate the differences between these two vaccines? Which one is currently being tested and considered for authorization in the coming weeks? What makes the two different, is that significant?

I did not previously realize that Johnson & Johnson is developing and testing two or three separate vaccines: JNJ-78436735, Ad26COVS1, and Ad26.COV2.S. Basically, my question is about which one is planned for use, and what are the differences between them?

submitted by /u/ano1067
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Does widespread immunity decrease virus mutation rates?

Posted: 26 Jan 2021 02:52 PM PST

With ongoing news about mutations to the covid-19 virus (and potential impacts to vaccine programs) I'm curious what the relationship between the level of population immunity and mutation rate is. It would stand to reason that lower infection rates -> fewer opportunities for mutation -> greater long term vaccine efficacy; but of course what's intuitive isn't always right.

Are we in a race to get ahead of mutations, or does it not really matter?

submitted by /u/fishsticks40
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How and why did they detonate the little boy 580 meters above Hiroshima?

Posted: 26 Jan 2021 09:59 AM PST

Multiple vaccinations for same disease?

Posted: 26 Jan 2021 08:02 PM PST

What would happen if someone was administered multiple vaccines for the same disease?

For example, for Covid-19, we have the moderna/Pfizer, astrazeneca-oxford, j&j vaccines which differ from each other (I think). What will happen if someone received each of them?

submitted by /u/anantj
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Why are some people unable to speak after a stroke?

Posted: 26 Jan 2021 10:45 AM PST

How fast did the Chicxulub Impactor appear as it collided with Earth?

Posted: 26 Jan 2021 05:54 AM PST

To an observer, did it travel like a bullet hitting a wall? Or like a cruise ship hitting a pier (slow velocity but huge momentum)?

The film Melancholia, for example, shows a relatively slow impact in the final scene. Definitely not "blink and you miss it"

submitted by /u/blishbog
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How do debris/people move back into the ocean during tsunami?

Posted: 26 Jan 2021 07:35 AM PST

I understand that it is a wave phenomenon and water currents but I can't seem to grasp why like in events or tsunami the debris flows back into the ocean?

submitted by /u/hus1999
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