swansont

Are you arguing philosophy or physics? Last I checked, gravity was in the realm if science. IOW, what evidence do you have that e.g.an electron doesn’t experience gravity? And if they don’t experience gravity, do they also not exert gravity?

Two clocks in relative motion will have symmetric time dilation values, based only on their relative speed. One clock has a different mass than the other, so they do not have the same momentum. It has to be a separate effect.

That's not enough. This is physics; we quantify things. Is the amount of dilation from the momentum equal to the amount you'd get from gravitation? (AFAICT the answer is trivially no, BTW)

That’s for you to show.

What paper? Is there a link?

A radiometer such as the one that was depicted does not work by radiation pressure. It rotates in the opposite direction. I don’t see that there is a connection here with a light clock, which is an idealized device and shows time dilation’s relationship with length contraction (owing to the invariance of c), rather than any real processes.

Yes, that’s what relative means, That specific comparison is not what is meant by absolute. For example, observer C will not get the same answer. When different observers get different results, the results are relative. So yes, you need to pick a new term.

Delberty has been banned for repeated violations of civility rules and not arguing in good faith.

Explain how time dilation makes me fall down.

Add me to the list. Clock rates are relative to your position in the well.

There's a reason for that. Only radial movement gets you to a different gravitational potential. Your use of "absolute" here is not in keeping with how relativity uses it. Pick different terminology.

If you take Myclock - Yourclock, the difference has a different sign for the two observers. And neither one can say theirs is "the" correct one

pi * diameter does not get you an area. Wrong units. A = pi * r^2 = pi * d^2/4

Wind tunnels literally have fans like this, but irrelevant if you are getting the same airflow from multiple fans. The air speed will be the same if you are moving the same amount of air through the same area. But if the air is moving slowly, it will not get sucked out of the top quickly. Here's where analysis comes into it, where you can avoid making potentially contradictory statements like this. Continuity matters in situations like this. You can't be moving more air in than you are moving out. Moving the air slowly is not in keeping with your desire to move air away from people quickly. Wild-Ass-Guess i.e. a proposal with no basis in modeling or analysis I suppose I was thrown by your statement in the OP where you said "You want the air to circulate so fast that if someone sneezes the water droplets will remain inside the room only a few seconds before it is sucked out the ceiling vent. " I've been basing my responses on what you said. Is this the scenario, or not?

Energy efficiency would seem to be orthogonal to the discussion. Airbrush seems to be implying that a large area of small fans somehow inherently gives rise to a different flow rate than a large fan "All I can say is if you have many vent fans sucking air out the ceiling, rather than one big fan that creates a wind tunnel, you distribute the motion and increase the area of the air moving up and out the ceiling." Changing the are will matter, but in the above quote it's not at all obvious that the example is changing the area (from the term "big fan" and that wind tunnels generally have a fan as big as the tunnel) It's the speed of the air that matters. The speed of the air being greater near a nozzle is only true near the nozzle, and it's not a given that there is any nozzle in this problem. Mainly what I want is Airbrush to present some science or engineering to back up a claim, rather than a WAG. This being a science discussion site and all. The scenario is proposing that air is only around for a few seconds, which sounds like you are getting 10 or so room changes per minute, instead of per hour. To do this, the air has to move faster, regardless of how you do it. My point is having the air move 60x faster is not an imperceptible change, as was claimed.

Changing the question doesn’t make the answer correct.

You said yourself a wind tunnel has a big fan. Where is the constriction? I ask again: how is one big fan vs lots of small fans different? (same area)

How is one big fan vs lots of small fans different? If you can’t model the behavior, how can you predict what happens?

How about some math/modeling to back up this claim

Most commercial places have ventilation systems that do up to 10-20 air changes per hour. A restroom might do 30. That means the air hangs around for minutes https://www.engineeringtoolbox.com/air-change-rate-room-d_867.html https://en.wikipedia.org/wiki/Air_changes_per_hour Which means that you need a flow rate that is much higher if you want air to only hang around for seconds. That's not "unnoticeably faster"

Retro-fit assumes you have a compatible geometry. What if the ductwork is in the walls?

How realistic is it to expect everyone to re-install their entire HVAC system? At best this would apply to new construction, in places where people don’t mind hanging out in a wind tunnel.

Claimed without support. Faster moving air means the virus can travel further before leaving the room, per the paper I linked to. Meaning you might infect everyone before getting a chance to filter the air. Hot air rises, so exiting through the floor isn't always the best option.

Not the problem described in the paper, which derives from in-room circulation. The air flow from the ventilation system assisted in getting the droplets to travel from table to table, before they would have had a chance to be filtered. We had a high-level person who insisted on stepping over the mats whenever he entered our lab. Grrr. (A tad like Pence not wearing a mask at the Mayo clinic) Anyway, I took to calling it admiral-paper. (And our visitors were referred to as sneetches, from the Dr. Seuss story)

I think even Iowa has cities.