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You can only sense the expanse of space because of objects in it, i.e. the observables are objects, not length itself. Just like the fact that your location changes lets you sense the passage of time.

I wouldn't bother with it. The dirtiest things you touch on daily basis without sterilization are paper money and door handles. If you wash your hands regularly, don't smoke, and don't put your hands in your mouth (child), you are relatively safe if you don't have severe immune system problems. One way is to use UV light. There are ready-made devices. There is also Sun.. https://en.wikipedia.org/wiki/Ultraviolet_germicidal_irradiation https://en.wikipedia.org/wiki/Germicidal_lamp I just found that local library has such device which also opens pages and use UV light on them.. https://www.google.com/search?q=sterilization+uv+light+books

Its the opposit which I reduced an alkane to an alkyne. You reduce the alkyne to the Alkane.

I would expect it to be the same mechanism, just in 2 stages, with an alkene as the intermediate step. In both alkynes and alkenes you have π-bonds which can bind to the metal surface. Kinetically, I imagine it may be a bit faster for alkynes, as they can approach in any orientation and still bind to the surface. There are descriptions of this on the internet. Here is one: https://www.masterorganicchemistry.com/2011/11/25/hydrogenation-alkenes-palladium-on-carbon-pdc/. This link suggests that alkynes are more readily reduced than alkenes. The only respect in which I think the mechanism you have drawn may not be quite right is that, according to my understanding, the alkyne or alkene itself binds to the metal via its π-bonds, whereas you have shown the molecule staying above the H atoms, rather than binding to the surface itself before reacting. (There is a diagram of the mechanism in the link.)

Sorry, I have not been able to keep up with these discussions over the last few days, as I’m busy with a large RL project. What was the question here? deSitter spacetime has non-zero Riemann tensor, so it’s not flat.

Painter's tape. Over here, it's blue and has the feel of masking tape, but you can use it to mask what you don't want painted and later peel it right off.

A Post-it note? https://www.staples.co.uk/office-supplies/writing-supplies/correction/post-it-cover-up-and-labelling-tape-25-4mm-658h

Had the Moon disappeared more than 4000 4.109 ya it would have been much much worse. Most Earth scientists think it was essential in the appearance of life. Or SpaceX.

Because science isn’t here to conform to your preferences. The world doesn’t revolve around you. The people who actually do science get to name things. Sometimes names provided by others stick, and inertia takes over. None of these avenues (or other possible ones) involves consulting you for approval. Perhaps a unit of hubris could be named for you.

Like in paradise? There were cultures that never moved away from Africa and had year-round abundance of food, so didn't had to develop modern agriculture, that lived in peace for thousands of years and didn't develop much in the way of military, compared to their offspring who moved north over the millennia. When they encountered the returning conquerors from the north, they were unable to fight them and were easily conquered. When I first read your post, the first thought that came to my mind was "life feeds on life" This is a primitive stage of development, which was widely expressed and condemned by Q in Star Trek The Next Generation. What about the Ten Commandments? What about the criminal or civil code? If they are simply contrary to all nature.. ? In "thou shalt not kill" there is no mention of who should not be killed.. there is no mention of it being a human being, there is no mention of it being an animal.. there is no mention of it being a plant or any other living being.. Paraphrasing, "If you killed a person, you are a murderer and go to jail after the sentence. If you have killed millions, you are just a successful politician".. It is doubtful that such a politician ("king" etc.) coming to church, after killing and being the cause of death for thousands of people daily, weekly or monthly, would even mention this as his or her sins..

Here are a few of mine: 1. "SAGITTARIUS A STAR" This title bothered me for many years until I figured it out. Why do they call a supermassive black hole a "STAR"? Black holes are NOT stars! Then I finally realized it means "Sagittarius A ASTERISK." That is dumb. Call it "Sagittarius A Hole". 2. Why not call: Dark Matter = Unknown Gravity? Why not call: Dark Energy = Space Energy? Because no can do, we must stay with the original racist terms. 3. Why RPMs? That means either "revolutions per minute" or "rounds per minute." Call it something people, such as I, can relate to. Say "RPS" or "revolutions per second" and "rounds per second" to save your reader from the doing math, dividing by 60, to figure out how fast that is. A second is very easy to understand. A minute is way beyond comprehension, unless you are a science expert. Don't get me started with "megaparsecs" or "astronomical units" when you could easily use "light years" or "light days" or "light minutes" which are FAR EASIER for most people to visualize. 4. Pedestrians who leisurely cross the street paying no attention to cars waiting for them. Any others?