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Saturday, February 19, 2022

Since the placebo effect is a thing, is the reverse possible too?

Since the placebo effect is a thing, is the reverse possible too?


Since the placebo effect is a thing, is the reverse possible too?

Posted: 19 Feb 2022 04:35 AM PST

Basically, everyone and their brother knows about the placebo effect. I was wondering, is there such a thing as a "reverse placebo effect"; where you suffer more from a disease due to being more afraid of it?

submitted by /u/MadMax2910
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How does drinking water immediately invoke a sense of your thirst being quenched?

Posted: 18 Feb 2022 10:00 AM PST

Since the renin-angiotensin system that triggers the thirst response occurs in the kidneys and would probably take a while to react to increased water, is there some kind of sensor in the stomach or something that lets your body know that water is on the way?

submitted by /u/silverhub89
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(Nuclear Physics) Does the fission of Uranium 235 release all of its binding energy?

Posted: 18 Feb 2022 09:53 PM PST

First off, forgive me if my terminology is off or if I've completely misunderstood something, nuclear physics is still new to me.

So the mass defect of Uranium 235 is ~3.082*10-27kg, which is equivalent to 2.77*10-10 joules, or the binding energy of 7.6 MeV per nucleon. Is all of this energy released when this atom is fissioned into krypton and barium?

On top of this, how energy efficient are modern nuclear plants? (i.e. how much energy is lost in the process instead of turning water into steam?)

submitted by /u/jamx02
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Could a nut and a bolt made of perfectly rigid materials be tightened together?

Posted: 19 Feb 2022 07:42 AM PST

Lets say we have mathematically perfect, rigid material and you make a nut and a bolt out of it - could the two be tightened together?

Im asking because I noticed that good quality nuts and bolts screw into each other with little to no resistance and only become tight once maxed out - what exactly happens at the last bit and why it gets tight? Im assuming the materials get ever so slightly bent, deformed and thats what makes it tight?

submitted by /u/KaktitsM
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Do organ transplants and blood transfusions cause mitochondrial chimerism?

Posted: 19 Feb 2022 07:40 AM PST

Blood and organs contain mitochondria, when they are introduced into a new host, is there a mechanism to prevent their proliferation and interaction with host mitochondria? I can't find research on this topic.

submitted by /u/baconn
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How precisely do we know when the asteroids that caused the end cretaceous extinction hit?

Posted: 19 Feb 2022 05:30 AM PST

Like was it 66.0 MYA, 65.4, 66.8 etc

submitted by /u/MiniHamster5
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Does climate change have an impact on winds?

Posted: 19 Feb 2022 05:19 AM PST

I don't know a lot about winds or what makes up a wind.

I saw recently UK has been having highest ever recorded winds. Which made me wonder, are winds affected by climate change? Are melting ice caps and other destruction of environment affect how fast wind becomes?

submitted by /u/World_Voyager
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Is obesity a cause of or a symptom of poor health?

Posted: 19 Feb 2022 05:47 AM PST

I recently saw a post on r/confidentlyincorrect which has a video of a woman saying that losing weight does not improve a person's health, and that a healthy diet and regular exercise should be the goal instead. In the comments some people are arguing that if you eat better and exercise more that you will lose weight, so that means losing weight must be healthy. This got me wondering: Is obesity in itself a cause of health problems, or is an unhealthy lifestyle the cause of the health problems and obesity is simply another symptom of this lifestyle?

Let's say there is an obese person who is very sedentary and eats a diet consisting entirely of highly processed foods. If this person were to lose weight by reducing the overall amount of food they eat, but eating the same foods and maintaining the same activity level, would this improve their health? Alternatively, if this person were to make no diet or exercise changes at all and were to lose weight by taking diet pills, would this improve their health?

Thanks in advance for your answers!

submitted by /u/SoupFlavoredCockMix
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Are hormones produced once a stimulus triggers their release or are they produced ahead of time and stored somewhere?

Posted: 19 Feb 2022 05:32 AM PST

I looked it up and found a lot of stuff about "secretion". Does that mean the respective glands are pockets that "hold" hormones and then just let them seep out whenever necessary? It would boggle my mind to know that hormones can be produced as quickly as e.g. a rush of fear hits you.

submitted by /u/leapfrog__0
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How efficiently does transfected mRNA produce protein compared to endogenously synthesized mRNA?

Posted: 18 Feb 2022 05:02 PM PST

I've been reading on all the proteins RNAs pick up on their way out of the nucleus, as well as pioneer round translation. I'm wondering how much impact those have on the eventual protein expressivity of the mRNA compared to a more "naked" mRNA that is transfected or injected in.

Of course there all all kinds of tricks with codon optimization, UTR structures, modified nucleosides, etc that can improve translation. But I'm talking about identical mature mRNAs, both capped and tailed identically.

Has anyone ever directly compared how much protein you make from an in vitro transcribed mRNA transcript versus an endogenously transcribed one? No luck finding any papers on the matter.

submitted by /u/thebiotechnologist
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Can a mountain have no rain shadow?

Posted: 18 Feb 2022 05:40 PM PST

So I understand that warm and moist air come up from the sea and make precipitation on one side of a mountain, but what if there's two warm currents on either side?

submitted by /u/Blackened_King
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What do we know about porn effects on chimps or other non-human primates?

Posted: 18 Feb 2022 09:37 PM PST

Do they have favourite style or genre? Does porn causes erectile dysfunction in chimps?

submitted by /u/gjvnq1
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Friday, February 18, 2022

Does the auditory nerves activate, when we hear the voice of our thoughts?

Does the auditory nerves activate, when we hear the voice of our thoughts?


Does the auditory nerves activate, when we hear the voice of our thoughts?

Posted: 18 Feb 2022 04:00 AM PST

I was wondering whether the nerves that are firing when we process sound activated, when we "hear" sound in our mind. Same could be asked for visualizations.

submitted by /u/Amitez0410
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If a nuclear payload was inbound via ICBM, would a ground observer be able to see it coming before the explosion?

Posted: 18 Feb 2022 04:13 AM PST

How does the immune system work outside the bloodstream?

Posted: 18 Feb 2022 04:02 AM PST

I know we have white blood cells and other immune cells floating around in our bloodstream that attack pathogens, but how do our bodies fight infections that occur outside the blood vessels?

submitted by /u/smackaroni-n-cheese
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How do steroids treat autoimmune disease?

Posted: 18 Feb 2022 09:00 AM PST

Why can’t propranolol lower blood pressure in type 1 diabetic patients?

Posted: 18 Feb 2022 07:08 AM PST

Is there any way to use the polarization of electromagnetic radiation to transmit information?

Posted: 18 Feb 2022 01:54 AM PST

I'm currently educating myself about electromagnetic radiation, mostly with a focus on environmental and health concerns, but hopefully with a solid physics background.

I just read about how EM-waves are modulated in three ways for the transmission of information in technical applications: amplitude modulation (AM), frequency modulation (FM), and phase modulation.

Light is also a kind of EM-wave, and I remember from chemistry class, that light has another characteristic feature: polarization. I suppose this also applies to other kinds of EM-waves.
Is there any sort of application, where the polarization of EM-Waves (like radio waves) is used to transmit information? Is this even theoretically possible?

I would really like to learn more about this subject. So please enlighten me! (pun definitely intended)

submitted by /u/schmegwerf
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Does working out specific muscles as a child cause those muscles to be bigger or more defined permanently as an adult?

Posted: 18 Feb 2022 02:29 AM PST

I'm probably not wording this right, but say you ride a bike in a really hilly area for years as a child and you develop large and strong quads and calves from it, are you more inclined to have bigger leg muscles, naturally throughout your adult life?

I know a few people with naturally big, specific muscle groups, and I when I ask if they work out those muscles the answer is usually no, but that they did some kind of activity as a kid which made those muscles big, and now they're just naturally big forever.

submitted by /u/Art3sian
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Why do muscarinic agonists have bad side effects compared to adrenergic agonists?

Posted: 18 Feb 2022 07:09 AM PST

Food safety sources often say that re-cooking questionable food isn't safe because, although it may kill bacteria, the contaminants could have produced "toxins" that won't be destroyed. Is this true? What are some examples of this?

Posted: 17 Feb 2022 08:59 PM PST

You made a mistake with your food -- you left it out too long, or cooked it at too low a temperature. But it's not salvageable. You have to toss it, because while re-cooking it properly may kill bacteria, it won't remove the "toxins" they could have produced.

I've seen this many times over the years and it always seems like folk wisdom that's repeated without a complete understanding. I've never seen an example of what these toxins may be or what contaminants may produce them.

Suppose some meat was left at room temperature for 24 hours, well outside the FDA "danger zone" (40 to 140 °F for more than 2 hours). If that meat is then thoroughly cooked at high temperatures for an extended period of time, what specific risks remain?

I would guess there are also factors involving bacterial population... i.e., eradicating a large population of E. Coli that grew over 24 hours is maybe more difficult than killing a smaller infection. But I'm specifically interested in the idea that bacteria or other parasites may produce byproducts that go on to survive a thorough cooking.

submitted by /u/pseudoorbit
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Do turtles have different blood types like humans?

Posted: 17 Feb 2022 11:06 PM PST

If you could, theoretically, inject live cancer cells in a body would that person get cancer?

Posted: 17 Feb 2022 11:13 PM PST

Thursday, February 17, 2022

Does leaving water in the kettle accelerate the formation of limescales?

Does leaving water in the kettle accelerate the formation of limescales?


Does leaving water in the kettle accelerate the formation of limescales?

Posted: 17 Feb 2022 04:42 AM PST

Our kettle is building up limescales very fast due to the hard water.
The question is if leaving remaining water in it is considerably accelerating the process. Residual water will slowly evaporate and leave it behind.

On the other hand, temperature decreases the soluibility (e.g.) of CaCO3, causing precipitation (?).So is the formation of liimescales due to the boiling process or leaving water in the kettle?

submitted by /u/mojonrgy
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Would antivirals prevent you building long term immunity?

Posted: 17 Feb 2022 03:50 PM PST

Using antivirals would kill off the virus before your body could mount an immune response and start producing antibodies so would this not negatively affect your long term immunity towards the virus?

submitted by /u/ConstantGuest6999
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What does "cooking" dynamite into "grease" mean?

Posted: 16 Feb 2022 07:12 PM PST

Big fan of Prohibition-era non-fiction and in a memoir I read of a safecracker, he talks of the explosives -- aka "grease" -- he would use to open safes:

"Shooting a box is real touchy because the grease that you're using is cooked out of dynamite and it's not the same consistency as nitroglycerin that you buy. Sometime it may be real strong and next time weak and there's no way to tell until you try it out."

He doesn't mention anything else about it and I've Googled this from every angle I know how. What does he mean by "cooked"? Literally, in an oven or on the stove? What is all even in that "grease"? Is it soupy or solidified?

EDIT: I'm now aware of Nobel having made nitroglycerin safer by inventing dynamite so that's cool.

submitted by /u/Chaloby
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Are There Any Invasive Species that Originate FROM Australia?

Posted: 17 Feb 2022 05:08 PM PST

We hear all about the invasive species in the land down under; from its toxic cane toads to its out of control rabbit populations, but is there any plants or animals from Australia that are invasive anywhere else in the world?

submitted by /u/1fishmob
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(Geology) The "polar wander hypothesis" was debunked, but isn't the phenomenon of a wandering pole an actual thing since we've observed that magnetic North moves?

Posted: 17 Feb 2022 04:55 PM PST

My textbook says

As paleomagnetists sampled and measured older and older rocks, their results seemed to show that the north magnetic pole was far from the modern pole and appeared to wander through time. This was called the "polar wander hypothesis" at first. But then they ran into a problem. Each continent had a completely different polar wander curve, which only converged on a common magnetic pole today. These data seemed to suggest that the magnetic field had behaved very strangely in the past, with multiple directions of magnetic north that no longer exist. As outrageous as that idea seemed, the only alternative was just as radical: the continents had moved through time, so it was not the magnetic pole that was changing but the continents that recorded their directions. But when you lined up the polar wander curves for two different continents, like Europe and North America, you found that they matched once you moved the continents back together as Wegener had suggested. In other words, the "polar wander curves" were only apparent polar wander curves because it was the continents that moved, not the magnetic poles.

What I'm confused about is my book saying, "the continents had moved through time, so it was not the magnetic pole that was changing" because isn't that not completely true since magnetic North DOES move? We've observed this movement, so isn't my book completely dismissing the idea of a "wandering pole" incorrect?

Everything I've watched and read online only talks about the effect of continental drift on the apparent wander curves, but they haven't talked about how the magnetic North pole does, in fact, move. Can't the movement of the magnetic North pole have had at least a tiny influence on the polar wandering curves?

submitted by /u/sinecosx
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Why do levels of procalcitonin increase during a bacterial infection?

Posted: 17 Feb 2022 06:30 AM PST

I know it rises because of the inflammatory response, but it doesn't lead to more calcitonin or decrease blood calcium levels. So what is it doing?

submitted by /u/Internal-Leek-2081
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Do other animals perceive taste like we do (Sweet, spicy, salty, bitter, sour and umami)?

Posted: 17 Feb 2022 06:58 AM PST

Can we repair damaged nerves?

Posted: 17 Feb 2022 04:09 AM PST

If yes, which ones and how?

submitted by /u/easyritirana
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How does stretching actually make the body more loose and flexible over time?

Posted: 16 Feb 2022 04:44 AM PST

I recently started kickboxing and I'm extremely stiff. However, my legs are gradually becoming more flexible and i find the process fascinating!

EDIT: Wow thanks for all the interest everyone, learning a lot. It's kinda crazy we still don't have the complete facts about how muscles become flexible through yoga and stretches.

submitted by /u/samedwar
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If mouthwash kills 99.9% of bacteria, why do we still have to brush our teeth?

Posted: 17 Feb 2022 08:48 AM PST

Mouthwash with alcohol in it allegedly kills 99.9% of bacteria.

If bacteria are responsible for tooth decay, why isn't it enough to just rinse with mouthwash? Why do we also have to brush our teeth? Can we not stop tooth decay with mouthwash alone?

I can see how flossing still makes sense -- to ensure the alcohol can get in between the teeth. And I know rinsing with alcohol every day is not necessarily good for your oral cancer risks. But I'm just curious.

submitted by /u/12_Yrs_A_Wage_Slave
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Just saw a post linked to a news article saying scientist found some planet 117 light years away in the Goldilocks zone, my question is how important is it to have a moon? Would it be habitable without one still?

Posted: 17 Feb 2022 02:56 AM PST

Two balls rolling down a hill. Which one is faster?

Posted: 17 Feb 2022 02:55 AM PST

Two identical size but different mass balls rolling down a frictionless slope. Which one wins the race? Looking for an answer to settle an argument among sone cyclists please.

submitted by /u/Ok_Anything_3239
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How can recombination happens between 2 covid variant?

Posted: 16 Feb 2022 04:58 AM PST

I can understand how recombination can happen very easily in influenza since their genome is segmented, but how is recombination possible for covid, which is single stranded

submitted by /u/DoBestWifWtGodGivesU
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does cancer need to display antigens for killer T cells to recognize it? And do natural killer cells recognize it without it displaying antigens?

Posted: 17 Feb 2022 01:11 PM PST

How did the Human Genome Project tackle the issue of mutation?

Posted: 17 Feb 2022 10:02 AM PST

When sequencing the human genome, would random mutations in any one human's DNA have affected the results? Did the scientists sequence the genome of several humans' DNAs to address this problem?

submitted by /u/koons_fan
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How did insects reach Hawaii?

Posted: 17 Feb 2022 02:03 AM PST

Or any other volcanic/atoll islands in the Pacific? It seems like the distance needed to cover are far too much for any insect to cover. And unlike say the Americas or Australia, which were at one point a part of Pangea, many of the volcanic islands are "only" a few million years old, and never formed as part of a continental landmass. So the insects had to somehow migrate.

How did insects come to colonise these islands? Hawaii is thousands of km away from North America

submitted by /u/nikolakis7
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How come different allotropes of Carbon have different Molar Masses?

Posted: 17 Feb 2022 01:40 PM PST

Why does Antiphospholipid syndrome result in a prolong PTT?

Posted: 17 Feb 2022 01:11 PM PST

I'm confused about it's role in the Intrinsic coagulation pathway that causes this prolong PTT

submitted by /u/twopeas_onepod
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can free groups of different (infinite) sizes be isomorphic?

Posted: 17 Feb 2022 03:14 AM PST

Let a and b be cardinals.

I can prove that for the free group on a and b generators to be isomorphic, 2^a = 2^b. So assuming the generalised continuum hypothesis, the free groups on a and b can only be equal if a and b are equal. However, there are models of ZFC where GCH is false. So are there models of ZFC or ZF where two free groups on different sized sets are isomorphic?

submitted by /u/deaths_accountant
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are the palm trees native to the americas related to the ones in places like the middle east?

Posted: 16 Feb 2022 09:52 PM PST

is palm tree just a word used to describe the shapes of trees that happen to look alike or did they somehow spread all over the globe?

submitted by /u/ventaline
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How does the international space station get fresh air?

Posted: 16 Feb 2022 04:45 PM PST

Forgive me if this is a stupid question but I was wondering what process they use to get oxygen up there.

submitted by /u/ZaydenO
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Is Montessori's "Sensitive Phases/Periods" an accepted concept? Alternatively: Is it possible children never catch up something they didn't learn at the right time?

Posted: 16 Feb 2022 10:06 PM PST

This came up in a conversation with a coworker about the Corona lockdowns. She claimed that children would have life long deficits in speaking, mimicking, etc. because when they don't learn such things at the correct time, it's almost impossible to catch up to the usual path.

I doubted that because I thought those skills are rather being improved thw whole life, but had no experience with children and related science. I only found out that goes back to Montessori when I googled it - and then I realized I ONLY find Montessori schools or forums on that topic but no studies or else.

Are there scientific studies/theories/experiments that support or deny that claim?

submitted by /u/Estesz
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What's the highest theoretical energy density for a battery?

Posted: 16 Feb 2022 11:36 PM PST

What is the highest theoretical energy density a chemical or otherwise battery (nuclear, fuel cell, etc) could achieve?

submitted by /u/t-cell-baum
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How has the Saharan Desert changed in response to climate change?

Posted: 17 Feb 2022 12:08 AM PST

And how is it projected to change in the future?

Could the climate change actually cause it to become a lush rainforest once more?

Or will it become even more uninhabitable than it already is?

submitted by /u/breh2022
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What's the difference between free-free and Thomson scattering within stars?

Posted: 17 Feb 2022 03:37 AM PST

I get the difference between bound-bound, bound-free and free-free scattering processes, but I don't really understand what sets the last and Thomson scattering apart. Note that I'm still unfamiliar with Rayleigh and Compton scatterings, so feel free to expand upon those if needed. Thanks in advance!

submitted by /u/itsOkami
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Tuesday, February 15, 2022

When the heart beats faster, the contractions are closer together in time. But is each contraction itself also faster?

When the heart beats faster, the contractions are closer together in time. But is each contraction itself also faster?


When the heart beats faster, the contractions are closer together in time. But is each contraction itself also faster?

Posted: 15 Feb 2022 02:04 AM PST

One of my students asked this the other week, and it triggered an intense debate in the classroom. Either answer feels fairly credible! I promised I'd try to look it up, but Google hasn't been very helpful, and a family member who's a medical doctor also wasn't completely sure.

It seems to me that since each contraction is coordinated by an impulse traveling down the heart from the SA node, those impulses would need to travel at variable speeds through the cardiac tissue if the contractions were to vary in speed, which feels unlikely?

submitted by /u/mabolle
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Why does the immune system specifically attack the joints in rheumatoid arthritis?

Posted: 15 Feb 2022 07:42 AM PST

Why doesn't it attack (for example) the stomach or the thigh?

Edit: thanks for your answers!

submitted by /u/TrueAbbreviations491
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Why are UHF TV antennas (almost) always loop antennas, vs. VHF antennas which are usually whip antennas?

Posted: 15 Feb 2022 09:38 AM PST

How does velocity through space affect perception of time?

Posted: 15 Feb 2022 12:38 PM PST

Hello, me and a friend were just watching some vids about time dilation and me and my buddy are trying to figure out where our logic is wrong here, so it would be great to see what we are missing.

Understandings:

When moving at the speed of light away from a clock, the clock would be perceived as 'frozen' to the travelling person's eyes.

What I don't understand about this is that, from what I know the way the eye works is that light must hit the retina for my brain to perceive an image. But surely if I'm moving away at the same speed the light is (both constant speeds), then the first bit of light might hit my eye, but after that there is no distance being made between the light and my eye since both are the same constant speed (for example 2 cars travelling in front of each other in the same direction at the same speed would never actually hit). Surely nothing would be hitting my eye anymore.

What am I missing here?

I have heard a lot that time dilation is just perspective, just like when I mentioned above, time seemed to be frozen due to moving away from the clock at the speed of light.

What I also don't get about this is that, time 'seems' to be frozen, however this is just because the light is not given the chance to hit my retina, surely that's just a visual effect. I have heard that time dilation could theoretically affect how you would age compared to another perspective, but I just don't see how that is the case since everything is to do with 'perspective'.

Surely travelling away from that clock at the speed of light doesn't actually stop time for me as an observer, it just stops me seeing the light coming off of it which tells me the clock is ticking. When I return back to earth, everything would have aged the same amount as me?

Any comments or clarifications would be awesome! Neither of us study or work in scientific fields so I'm not sure if there is a relatively simple way of explaining this, but again any help would be really appreciated :)

submitted by /u/JoergenSchmurgen
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Could the rabies virus infect insects?

Posted: 15 Feb 2022 02:03 AM PST

If no, why? If yes, why isn't it that the virus spreads rapidly to all animals?

submitted by /u/SkullTune
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How do we know photons have no mass vs simply being so small we have no current way of detecting their mass?

Posted: 14 Feb 2022 10:12 PM PST

So I don't know a whole lot about partical physics, I only took a basic physics class at a community college so a simplified explanation would be best but:

How do we know that photons don't have a mass?

Could it simply be that they have a very small mass we simply haven't detected yet with current technology? And how do we know?

submitted by /u/new_usernaem
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How do gyroscopes work?

Posted: 15 Feb 2022 06:19 AM PST

What is it about rotating mass that creates stability? Also if speed depends on your frame of reference, do gyroscopes have a "universal" frame of reference in space? (I'm probably misunderstanding part of how that works)

submitted by /u/chandrian777
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Can you break down exactly what happens during serotonin syndrome?

Posted: 14 Feb 2022 09:47 PM PST

I'm having difficulties finding out exactly what happens in the brain during the whole process of serotonin syndrome so I'm wondering what exactly happened how does the poisoning happen just like the fine details of it

submitted by /u/RealisticBar7194
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Why does water have the highest density at 4 °C?

Posted: 14 Feb 2022 01:05 PM PST

What are the direct causes of inflation? Why does inflation happen so quickly?

Posted: 14 Feb 2022 12:10 PM PST

I've been trying to understand inflation for a while, but I can't wrap my head around what exactly makes it happen.

If a material becomes more scarce/abundant, it makes sense for its price to change. Would it not take time for that price change to reach the end products though? If we look at gas prices for example, why would they change every hour?

submitted by /u/38248619022577793790
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Does snow evaporate without melting?

Posted: 14 Feb 2022 01:26 PM PST

I live in a high desert with very low humidity (15%). About 50 cm of snow fell at the end of December. No new snow has fallen for 6 weeks and the temperature has never been above 0 C, yet the depth of snow has decreased to about 25 cm. What causes the depth of snow to decrease when it doesn't melt?

submitted by /u/HogSliceFurBottom
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If I had a lightbulb in a sealed box and turned it on would the light stay in the box?

Posted: 14 Feb 2022 10:49 PM PST

Where is the consciousness located?

Posted: 14 Feb 2022 10:53 AM PST

I watched a documentary on the topic then wanting to get more sources on the topic. Itwas harder then i thought and still have a hard time understanding what the scientific concensus is if there is any.

https://youtu.be/CmuYrnOVmfk The doc I watched talked about the brain stem area.

submitted by /u/cemilanceata
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