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On the contrary, I think he's turning out to be a great pope. Pope-same sex marriage Venezuelas Maduro, citing pope, asks congress to consider same sex marriage

Spacecraft during re-entry only get up to ~ mach 25, and even at that speed, the air is heated to a plasma state. Craft like Apollo and Soyuz use ablative shields that burn off to deal with it. And this is in the upper part of the atmosphere, where the air density is very low.

God bless. I’m in the middle of a self induced therapy of treating the conservative religious a little more politely. I don’t see much progress though and the prognosis isn’t positive.

Recently I returned to a discussion after a break and I was suddenly accused of not taking centrifugal forces into account. I guess I was out of the loop for a while.

It's the age of the extravagant conservative, the age of informed ignorance, filled with wasteful exploiters and passive despoilers. An age of boring amazement. Clearly it is the age of the Oxymoron.

Your error is that you again are not taking relativity of simultaneity into account. To illustrate, we can put clocks at the end of rod attached to B and at the point's along the rods. Thus from The E-X rest frame you get this: The green boxes indicate two clocks passing each other and their respective readings as they do. In the rest frame of B, you get this: Comparing the the times shown in the green boxes as clocks pass each other agree with those in the first image. In each image, there is a an instance when two pairs of clocks pass at the same time, but they are different pairs of clocks in each image. This just illustrates that, with the Relativity of simultaneity, events that are simultaneous for one frame of reference are often not simultaneous for another.

https://www.livescience.com/aliens-spot-earth-exoplanets.html

Anthro-dystopian

No, but how you come to a stop might. ( falling off a building never killed anyone; it's that darned landing that does )

You wouldn't feel any difference from standing still.

The fact that a re-entry vehicle is trying to slow down, and so presents a 'blunt' face to the atmosphere, is where most of the heating comes from. A 'streamlined' re-entry vehicle would hit the ground at thousands of miles per hour; the space shuttle re-enters bottom first to generate 'slow-down' drag, and the reason ablative tiles are attached to bottom surfaces.

All materials have their limits, ceramic plates like the ones used on the outside of the Space Shuttle or ceramic car brake rotors in performance cars will eventually vapourize in high enough temperatures. Air resistence would require you to use enormous amounts of fuel/power to propell something to Mach50 in Eatrhs atmosphere, that is if the construction of a your plane would even withstand the huge pressure (it wouldn't) Thats the reason why fast spy planes fly at high altitudes - less fuel needed at high speeds, less air resistence.

We're caught between how fast we can change things and how slow we need things to change. We need to behave differently but too many people want us to behave EXACTLY this way so they can make more money. Societies always have growing pains, and hopefully we can explore together a better direction than the one we've been taking. IIRC, you let the breeze get your hair caught in the trees, so you have only yourself to blame.

! Moderator Note Virtually impossible to discuss anything with someone who argues this way. These thoughts and phrases are obviously very important to the poster but mean little to us without context. Discussion is like serving a meal. You want to give your guests something they can sink their teeth into and enjoy focusing on the experience. This style is like trying to feed guests by making them catch popcorn from the stove in their mouths. Amusing to the host perhaps, but highly unsatisfying for everyone else. Mike12 will have to learn this elsewhere.

This a good thing. Being wrong is not bad but refusing to admit you are wrong is terrible. All the greatest physicist and scientists were wrong about many things, and learned from their errors. There is no doubt you have learned a lot of mechanics in this thread, I know I have. Thanks for the discussion.

This site. Scroll down about 1/3 of the page to find the diagram.

You're in over my head! Hopefully someone else can help? That's the derivative of a hyperbola. I don't see it saying anything about switching places. When y (or r) is small, it changes quickly. As y gets bigger, it approaches x (or ct), and the rate of change approaches constant; a unit hyperbola asymptotically approaches the line y=x. If you take the spacetime interval and make r a function of t, I think what that means physically is... It describes how the spatial distance of the interval changes as a function of the time component of the interval, as you go through different frames of reference. The infinitesimal changes in t for example would mean, if you change inertial frames by just a little (ie. with infinitesimal change of speed), the time and spatial distance components of the interval change like a hyperbolic function does. Or, an infinitesimal change in speed corresponds with an infinitesimal hyperbolic rotation of the spacetime interval. Edit: I'll leave that there but it's wrong! When both x and y are very large, an infinitesimal rotation (I think) can still mean a huge change in x and y. So to correct that: A small change in inertial frame involves an infinitesimal change in t and an infinitesimal change in r. However, as speed approaches c, a small change in speed (but huge change in rapidity) can involve a huge change in t and r. That makes sense with respect to velocity composition, right? Maybe it's correct to say "an infinitesimal change in rapidity corresponds with an infinitesimal hyperbolic rotation of the spacetime interval", but I might change my mind again after learning more...

Let's not reflect too hard on the CDC... circa early 2020.

Stellar size BHs ( from collapsed former stars ) tend to follow orbits around the galaxy, just like stars do. We have an equivalent chance of colliding with another star as we do with a stellar BH. Galactic core sized ( millions or even billion solar mass ) BHs are another matter. Although just about every galaxy has one ( or more ), to be ejected and become 'rogue', they need to be involved in a collision. Just how many galactic collisions are there ( or were ) within 100 million light years ? Not very many at all. Chance of one reaching our galaxy within a billion years, virtually nil. Although in about 4.5 billion years Andromeda will collide with the Milky Way, chances of stellar or BH collisions are very low. ( interstellar pace is HUUUUGE compared to the size of stars )

The Sun is a magnitude 5.8 star, barely visible from 50 LY distance. However, about 100 years ago, we started broadcasting information embedded in EM carrier waves out into the universe. Any advanced civilization residing on one of the 133 star systems within 50 LY, would have detected us 50 years ago, and their armada, travelling here at light speed should be passing the outer gas giants as we speak. Yeah, I'm joking ( maybe ).

Wait … Aren't we still in the Age of Aquarius ? Sex , drugs and Rock 'n Roll ? ( or is it just my weekend ) What does this mean ?

I guess that could be possible in some areas...we don't know exactly what the TOE is yet.

I'm at an age where I'm looking to find myself as I've always been and I'll always be. Szczęść Boże

The age of bumper sticker level analysis.

Possibly. If it passed in front of light sources we could notice that they had been blocked. We might be able to gain distance and velocity information from that blockage and from gravitational lensing. There would also be radiation given off from the accretion disk, as it gobbled up matter. But if it was "about to enter our galaxy" we would have many years to notice it. We're more than 10,000 LY from the edge radially, and several hundred LY from the top or bottom of our part of the disk.

Indeed. Only 37 times in 90 minutes. Someone should give that man a medal for so successfully lowering our expectations! If only he and his cult members realized not getting covid under control was damaging the economy so much more

My apologies I haven't chimed in yet. (I need to switch on notifications from this forum if that possible). To answer your question studiot, I don't have any more information - this was just a story told to me. What made me question it was the credentials of the guy who designed it, who I'm guessing know very little if anything about fluid mechanics. I just thought it was a very interesting problem. But as the discussion has unfolded - modelling the drain pipe as an open channel flow can get quite tricky. So details an assumptions about the problem are critical to solving it, which is what I thought. But thank-you all.

I would not necessarily agree with this - I think as you get older you develop more wisdom, but not necessarily intelligence. Exactly how do you define 'smart'? I think it is context and experience, which is something that can only be developed with time (and circumstance). For example, a young medic fresh out of university may know everything there is to be found in medical textbooks - but standing on the bedside of someone with (let's say) unusual or non-standard symptoms, he may still not be able to diagnose them correctly, since he lacks the experience to put that knowledge into a wider context.

Redlining and greenlining. Please explain. I grew up in what could be termed a ghetto or "hood" environment in Glasgow. I don't know what your background was, but we were all poor. The poverty was just a temporary shortage of funding as I understood when we grew up. Doctors, PhD's and scholars came out of that environment, yet a large portion of the people believe in the hype of the ghetto and what it is meant to represent - trying a little bit, failing and then giving up. That archetype is what dominates ghetto environments . The way out is to sell drugs and get rich quick, or die trying. The criminals offer young children a different role model of easy acquisition of wealth to surround oneself with wealth. This is an erroneous and dangerous mindset and philosophy passed on from father to son in my opinion. Please do elaborate on redlining and greenlining....

I would like to see a moderator say "No, you cannot talk about whatever you please; Answer the question." And if they continue with their talking points that have nothing to do with the posed question " So, you refuse to answer the question ? Let's move on." So that the audience understands the situation. Would have loved to see K Harris have a Biden moment, and tell M Pence "Just shut up, man !"

I had this thought which bugs me: "If absolutely nothing existed, reality wouldn't exist either. Therefore, absolute nothingness cannot be real. And thus, something has to exist." Thoughts? Can it stand as a logical statement? Why do you think there might be something instead of nothing?

Hi. Welcome. Very old question, but very difficult to answer nonetheless. So I'm going to get hold of some visual aids found on the web. Nothingness is quite easy to picture in your mind. Maybe we get that picture from our hours of sleeping without dreams. I don't know. But, The picture of the closest thing to nothingness that we can build from physics is not a featureless scenario. It's more like this: Or, more diagramatically, like this: A perpetual struggle of opposites annihilating each other. It just isn't just nothing. What it suggests is that what we call "nothing" is more like this ephemeral tug of war between ephemeral somethingnesses (virtual particle-antiparticle pairs). Nothing (in a poetic picture derived from serious physics) is a struggle between opposites in which nobody wins. At some point in the past, somebody won (why that was so is still an enigma; I don't like the word "mystery".) The status of the theory so far is that something like this sea of opposites annihilating each other must have fell downhill some kind of modulating field (inflaton field) 13 point something billion years ago, generating real particles and filling the universe with structure. That's called inflationary model of the universe. I hope that helps, but it's been a long time since Leibniz set that question to nowadays. So the story has become more involved.

You know exactly what they Were saying in those Soviet Republics, is that you're leveraging your money against the people. That's Exactly what the Communists are saying right now! You know I'd happily ball up 100,000 dollars right now of money from pure labor and hand it where I Want, and live the rest of my life in a car and bread loaves, has been foreseen, no complaints, and I'd also Happily Murder the Communists that are a total lie. Its the Same Thing! It is no Difference to what has ever been done by me or anyone around at any time. Someone Fibbing they'll Survive talking about how they have seen any assets used to leverage anything on anyone. You can murder these communists and ship them back to South Korea in repatriation in unmarked boxes to be filled in big mass unmarked graves, it'll have its own PO Box. With houses and such, its like the Gucci movie on TV, like impress people with Plans, OK?! Did I own my grandparents or any assets or ever have aggressive behavior or think I could or have a slightly off the floor bent over bow in my back about everything? Its bent over double that lies are more suitable to most people in their conscience. You know free speech is totally in danger with these and all your other rights, a total deprecation of all your rights will happen all at the same time.

Most scientists today are Asian since white kids aren't smart enough to outcompete them for spots in grad school.

Yes. No. Humans have an emotional capacity that facilitates a great range of behavior. You believe things as you need emotional investment in something for it to have relevance to you. ((Your answer, joigus.)) Yes, I anticipated you would think along such lines. You refer to some Popcul thing? **The negative rating by 'someone' I interpret as 'someone's pussy hurts'.