Evolutionary biology categorizes speciation by two organisms’ ability or inability to reproduce and have viable, fertile offspring. So, donkey and horse make mule but mule infertile, so different species. In biology we align DNA sequences to determine genetic similarity and can make “tree” diagrams demonstrating how closely related two organism might be. We can also look at enzymes two organisms share and the differences in their amino acid sequence but also physical structure but neither of these will tell you about whether two organisms are part of the same species, it tells you a beautiful story about evolution though

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I mean, so would artificial wormholes, but we have no idea how to make those either.
Speculative, non-existent technology is not the answer to "why haven't we done this yet". The jury's out on whether or not there's any way to circumvent the speed of light, but if there is, we've no earthly idea how.

Wouldn't the Curvature engine as we currently understand it, the Alcubierre Drive require more energy than the output of the known universe?

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Amount of blood vessels in area aka vascularity decides where would we administrator any parenteral product which includes vaccine. We want to it to get dissolved in blood to show it's effect, if there are a lot of blood vessels the distribution of vaccine/medicine will be faster. But vaccine isn't injected into blood directly since it's a killed antigen Or it's byproduct or any other live antigen, we want it to act slowly so given intramuscular, because if it went directly in blood the action will be faster that's the side effects I'm talking here like fever, etc who are going to cause problems. I've not heard or seen anyone administering vac in foot area though.

Would be super inconvenient if you get swelling and/pain.

Efficacy is impossible to know if not tested.

Vaccines are administered into a muscle because its a highly vascularized tissue. This means there’s a lot of blood vessels that supply muscle. Therefore, the vaccine can become detected by the immune cells in your blood and your body can initiate the immune process. You want to avoid administration into fat tissue because it is not as vascularized, leading to delayed absorption and possible denaturing (or breakdown) of the vaccine. The deltoid muscle of your arm is a great spot because it often has only a thin layer of fat and a thicker layer of muscle. This site has also been shown as a safe route because of the relatively lower risk in puncturing a major nerve. If you were to inject into something like a foot, you run the risk of missing a muscle and/or puncturing a nerve.

Would the center of the sole of the foot be an appropriate place to administer? I’ve heard of some people getting a BCG vaccine there due to the likelihood of it leaving a scar on the arm. Would that decrease efficacy?

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It's assuming identical conditions otherwise.

• Replace the ~1 meter antenna of a Mars spacecraft with a 500 meter telescope for a gain of 250,000.
• Increase the power from ~100 W to ~5 MW for a factor 50,000.
• Replace the 70 meter antenna of the Deep Space Network with another 500 meter antenna for another gain of 50.
• Replace the 1600 light years used for the 18 quadrillion number by 100 light years for another gain of 250.

Combined that's a factor 150 trillion, so we are only worse by a factor 100 or so. We won't get the multi-megabit connections we can get from Mars, but it's still good enough to transfer tons of information over time. There is no rush - it will take 100 years to arrive anyway.

There isn't going to be an abrupt cutoff between sound and not-sound, of course. But there'll be a range of pressures where it stops being as useful to think of the phenomenon as "sound" and starts being more useful to think of it as a vibrating thing occasionally imparting more/less energy to individual gas molecules.

My semi-educated guess is that's around when the mean free path of the gas molecules stops being small compared to the wavelength of the sound. But that's just a guess.

It has to be delivered intramuscularly. Any large muscle group will do, which is why we have a few spots to choose from - the upper arm, hip/glute area, thigh. Upper arm is easiest to do in the clinic typically although it's not abnormal to be asked to pull your pants down for shots! You can get more than just vaccines delivered via intramuscular route. Efficacy would be affected, yes, if the vaccine just gets into thick skin layers like in the foot.

What makes some people more susceptible to receiving static electric shocks compared to others in the same environment?

My dad says he has never experienced a static shock, while I have been experiencing it 5-6 times a day the past few days. Neither of us carry any metal regularly other than gold jewellery. I regularly moisturize my skin, my dad doesn't.

Is that 18 quadrillion number wrong then? Or what am I missing about that? Because that order or magnitude doesn’t even sound like a real number. If I’m counting zeros right, that’s 18 thousand million million times more power than doing it from Mars?

The primary reason for lower compression ratios on engines with forced induction is that the compression process (from turbocharger or supercharger) heats up the air, and even with an intercooler, the increased temperatures raise the risk of pre-ignition (or detonation, or knock). Higher octane increases the auto ignition temperature, allowing for greater pressures in the same engine without knocking. The engine static compression ratio can also be lowered to reduce how much the air will be heated by the compression stroke.

But this is actually not necessary. It is just an extra safety margin that is favored by people who really really don't want to take more risk than necessary. For example there is a turbocharger kit for the Porsche 11:1 CR flat 6. It is limited to 4psi, but it still provides a rather large increase in power, because you will make more power for a given boost pressure with a higher CR.

However... all of this is largely beside the point of your question. There is an easy way to shortcut all of the nuances of the variables when you are looking for cylinder pressures: Torque. More cylinder pressure = more torque on the crankshaft. So the way to get the answer to your question is to examine different engines with different CRs, different boost pressures, etc... And just look at what makes more torque.

I have had the same 1.8L engine boosted, and dynoed, at pressures from 5psi to 15psi, and with CRs of 10.5:1, 9.5:1, and 8.6:1. (and have had other non-boosted versions of the same car/engine) All on 93 octane, so that was a controlled variable. I could run more boost on track without knock with the 8.6:1, but the torque/power peaks didn't actually vary much. Naturally Aspirated doesn't change this. Cylinder pressure is directly related to torque.

Anecdotally, I vastly preferred lower boost and higher CR for a given power level, since the turbo reacted quicker from a higher off-boost mass going through the turbine, and when spooling it gets to it's lower peak boost much faster. The end result is that the car had much better partial and transient throttle dynamics, which made road course "racing" (non competitive) vastly better

Once, while tripping on acid, i managed to imagine a bird flying through the air and track it smoothly. Gf at the time noticed it and was like "IS THERE A BUG?!"

We could communicate with an alien civilization with Earth-equivalent technology over something like 100 light years. It's more difficult than communication with Mars - you need more power, larger antennas and you'll get a lower bandwidth - but it's possible. If the aliens have more advanced technology then the distance could be much larger.

AFAIK, mucous production occurs as a way to ‘trap’ pathogens. So yes, congestion is trying to do a good thing even though it’s unpleasant for us to deal with. This is why mucous can turn a certain colour when you’re sick, the pathogen can give it a particular appearance.

A lot of what you “see” is your brain filling in the gaps. So motion that ‘looks smooth’ isn’t necessarily because your eyes are tracking it smoothly, but because your brain knows what objects moving through space act like…

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First, we need to deal with the fact that there isn't a blackhole anywhere close. The closest is probably several thousand light years away. Basically, any blackhole is considerably beyond our reach. This is all before we can consider designing a probe that could somehow survive the trip there and then the immense gravity of the blackhole. Lastly, any information we could possibly gather would itself be trapped by the gravity of the blackhole.

TLDR: The distances are too great, nearly impossible to send the probe beyond the event horizon, and the information itself would be trapped with no escape.

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So does that mean all the SETI stuff is basically pointless? Is there even vaguely conceptualized broadcasting technology that could be built consistent with the laws of physics that could hypothetically reach us from another solar system?

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