Genady

Like any other mental disorder?

This little hospital has 16 rooms connected as shown in the picture. There is one patient in each room. The patients in the rooms 2 to 16 are bedridden, but the patient in room 1 is fine and ready to go home. This patient wants to meet every other patient once, and only once, and then to exit the hospital from the room 16, as shown. How can it be done?

Defined and realized are two different things. I am talking about realization, not about definition. My question was about mathematics. Things do not have measurable properties there. Let's take an example, the sum 2+3=5. It has part in your existence, it has no property to measure, it is absolute, sustainable, viable. It exists everywhere.

You mean about the time reversal? If so, yes. It is a universal causality relation between events.

Correct.

Here is how the masters explained it, from Misner, Thorne, Wheeler, Gravitation, p. 823. For clarification, r=0 is the BH center, r=2M is the BH event horizon.

After the first photon passes the vertical polarizer, the photons are not entangled anymore, and there is no further correlation between them regardless of what is done to any of them.

Right. I would put in a small print, "as long as we're talking about the black holes of classical general relativity". Consider this fact for example: the curvature is such that you would NEVER see anything falling into the black hole. You would see the things moving slower and slower and slower as they get closer and closer to the BH, never crossing the event horizon. Can the blanket demonstration demonstrate this?

So, you lie to poor children? 😄

On the #16 now. Most of the first third of the course, so far, is dedicated to questions and answers related to existence of God. This disappoints me.

The blanket will not wrap completely around the weight. It will wrap around its lower half and will go straight up from the equator, leaving the upper half open. So, nothing gets trapped inside.

What gravitational effect radiates from black hole at light speed? I can agree that it demonstrates that aspect of gravity. My 'displeasure' is that it does not demonstrate black hole.

I agree that this is good news. However, I am surprised. I don't know BSL and I know that it is quite different from ASL, which I am studying right now. I am surprised that BSL would require long spelling without special signs for these terms. For example, in ASL, I'd simply sign "green"+"house"+"effect", which are three very short and common signs. Here is the explanation of this effect in ASL, using only standard signs:

Which point? What consequence of gravity? What is the difference between this demonstration and a demonstration of a weight hanging on a spring? A heavier weight stretches the spring more. What does the blanket demonstration demonstrate that the simple spring does not? You put heavier and heavier weights on the spring, and at some point, the spring snaps. Does this demonstrate a black hole? How?

Consider a collapsing star of mass M, not a black hole. As it collapses, its size changes, but the mass stays the same. When its radius becomes smaller than 2GM/c2, it becomes a black hole. With the same mass. Did a correct point get across?

An unhappy continuation of the subject, There’s far more scientific fraud than anyone wants to admit | Ivan Oransky and Adam Marcus | The Guardian

I think that this demonstration is wrong for a number of reasons: 1. Blanket breaks. Spacetime does not. 2. The depression in the blanket is caused by weight of the object. A black hole is caused by its size. 3. The depression is caused not by the object's gravity, but by the Earth's gravity. 4. The blanket responds to the weight due to its elasticity. The spacetime does not. ...

Any sum? Could you give an example?

The blanket exercise demonstrates a breaking point. What does it have to do with black holes though? I mean, you got the Earth, the weight, and the blanket. What does the blanket signify? What does a depression in the blanket signify? Regarding the Hotel California, I don't see any similarity with the black holes at all. You could just use a mousetrap instead.

I watched it and liked it. A lot. I clearly remember that I liked it. Don't remember much more than that, but some vague images. Well, it happened before you were born ...

I get this in Edge sometimes. Also, sometimes, I can't Quote or Edit etc. In all such cases I reload the SFn site. In fact, "sometimes" is not rare at all.

In some fields, it is one in twenty. E.g., biology.

Union of Soviet Socialist Republics, which could be translated as Union of Collectivist Socialist Republics.

Thank you for the explanation. Yes, statism vs collectivism. Soviets stayed in existence and in the name of the country, powerless.