Re: "Where Is The Kinetic Energy of a Bullet Stored?"


jgreenfield@xxxxxxxxxxx wrote:
[snip for length]
> > Why should I respond to your refusal to punch numbers into a calculator
> > to check them. Do you deny that (1/2)(10 kg)(224 m/s)^2 = 2.5E5 J?
>
> My calculator must be fucked! It keeps coming up with sequence 25588
> NOT 25000

Well, yes, I'd say so. My calculator says (reading it blindly) 25088,
not 25588. However, I also know that I shouldn't be quoting an answer
to five digits, since the input digits are at best good to 2, and so I
rounded, which is the proper thing to do. If it makes you feel better,
assuming all the numbers in my example are good to five digits, then
the speed of the bomb hitting the ground is 223.61 m/s (which you could
have checked and which I rounded to 224 m/s). Now I invite you to
calculate (1/2)(10 kg)(223.61 m/s)^2.

> >
> BtW: Is the (10kg) as measured (weight) in the plane, or on the
> ground?

Since that's a *mass*, Jim, and not a weight, it doesn't matter where
that measurement is made.

>
[snip]
> > > Run the expanding chequerboard; now run it backwards.
> > > Is it collapsing to a POINT?????????????????????????????
> >
> > Yes, but you can't declare one point to be *stationary* without
> > reference to a space (the table) *outside* the checkerboard, and
> > thereby require that there must be some observable connection between
> > the checkerboard and this external space.
>
> Passing strange!?
> The expanding ruler you claim as evidence/model for BB, the SHRINKING
> one, NOT!
> (the chequerboard only being an extra dimension)

Well, *that's* a remarkable statement, considering that a shrinking
ruler is just an expanding one, run backwards through the film
projector.

> >
> > The customary thing to do here is to once again point to a spherical
> > *surface* which is expanding. To make this easier for novices to grasp
> > this, the spherical surface is often envisioned as being embedded in a
> > 3D space, where a center of the sphere that lies *outside* the surface
> > is apparent. However, where most novices stop short (and I guess I
> > would include you in this) is recognizing that the properties of
> > curvature can be determined entirely from the surface itself *without
> > reference* to the embedding space. Once this is realized, then the
> > embedding space and all features in it, including that "center" that
> > does not belong to the surface, can be dispensed with entirely.
>
> The whole scenario is nothing but imaginary, magical, mentally morphed,
> CRAP!

No, really, it's not. It's actually pretty straightforward, though it's
plain you've never been taught how to do this.

> I remember when Al S talked this rubbish re Mobius strips, and asked
> him to produce one which occupied 2D. Being a cowardly, indocrinated
> idoliser, he disappeared.
> FYI, without "reference" to the "imbedding space", the curvature cannot
> be determined.

No, really, it can. It's actually pretty straightforward, though it's
plain you've never been taught how to do this.

> There are NO 3D in 2D

You are under the mistaken impression that curvature is a feature of
the embedding space only. That's simply not true.

> >
> > Then the question is, if this surface is expanding, is there any point
> > *on the surface* that can be said to be the center of the expansion?
> > Though we can clearly determine that the surface is expanding (even
> > without invoking an embedding space), we cannot determine a center of
> > expansion in the center space.
>
> If you believe that the universe "curves back on itself", then every
> stellar object could be seen in more than one direction, appear to be
> at a different location, and at a different time. Is _that_ what you
> really believe?

Good, now at least you're asking for a confrontation of the model with
an experimental observation. However, you need to ask what the model
would really predict. For a universe that lives long enough, you are
exactly right -- we would see images of the same star from opposite
directions. However, if you take a look at the age of the universe and
how far we can see, you figure out that the light that goes the long
way around the closed universe (if it is in fact closed) hasn't had
enough time to make its way to us.

Moreover, I did not say that our universe is closed (positive
curvature), I pointed out how to take a simple example of curvature in
2D and apply the same lessons to a 4D space. There is evidence that our
universe is in fact open (negative curvature), in which case we will
never see light going "the long way" from a star.

> >
> > Similarly, we live in a curved 4D space, which we can ascertain is
> > expanding and which is curved, without any reference whatsoever to an
> > embedding space of higher dimension. And similarly, there is no point
> > *in this 4D space* that is the center of the expansion. One *could*
> > imagine a higher-dimension embedding space, and the center of the
> > expansion in this embedding space would be a point *outside* our 4D
> > space. However, this embedding space is by no means necessary, and the
> > physical reality of a center *outside* our 4D space is by no means
> > required. In any event, such a supposed center does not lie in our 4D
> > space, which is precisely the point I was making and which you fail to
> > grasp.
>
> What I "grasp" is that there are 3 dimensions for distance/direction,
> and a finite velocity of light with respect to time and its (light)
> origin.
> Time is NOT a dimension.

Really? Why not?

> >
> > > >
> > > > >
> > > > > Both
> > > > > > of you also accurately conclude that, assuming that the rate is
> > > > > > constant, some time ago, the whole ruler -- regardless of the length --
> > > > > > had zero length. In fact, if the time between these two observations
> > > > > > was T, then you both now this happened 4T before the first measurement.
> > > > > >
> > > > > > However, B sees himself to be the center of the expansion. You, at C,
> > > > > > see yourself as the center of explansion. This would no doubt be true
> > > > > > for a friend sitting at any mark on the ruler. And since there are no
> > > > > > observable ends to the ruler, the ruler might well be infinite in
> > > > > > length. Either way, it's impossible to determine a center of the
> > > > > > expansion, nor does there need to be one.
> > > > > >
> > > > > > If you think otherwise, where is it, and how do you know?
> > > > >
> > > > > George and I spent quite awhile on this:
> > > > > He suggested a chequerboard, with all squares moving away from each
> > > > > other.
> > > > > So I did it on the computer, and no matter how the squares moved, they
> > > > > always went on a line pointing back to a common origin. OK, so he says
> > > > > we'll look only at one square, and expand that, but we CANNOT ignore
> > > > > that this (group of dots) as a unit are STILL moving away from that
> > > > > initial common origin.
> > > > > Expansion DEMANDS a point of origin/center; it is always there
> > > > > (although studiously ignored/disclaimed by bigbangers)
> > > >
> > > > What makes you think the origin is common?
> > > > Why can't the center of each square on the chequerboard insist that it
> > > > is the one with the stationary origin? What experimental test do they
> > > > do to determine which one is the *real* stationary square?
> > >
> > > see above--run an epansion backwards!!!!!!!!!!!
> >
> > Exactly. *Each square* would see all the other squares collapse toward
> > it. There would be no way to tell if all the other squares are
> > collapsing toward you or whether you are collapsing toward another
> > square.
>
> Who cares if they have the same brick mentality as DHRs? Observers (and
> squares ) ARE MISLEAD/mistaken because things happen WHILE light is
> bringing information about PRIOR events/positions.

Really, what things are happening to the squares or the ruler markings
that are not reflected in the information carried by the light? And how
do you know?

> >
[snip]
> >
> > If you imagine something that is completely unobservable, then it is a
> > useless concept. If it is a useful concept, then it has observable
> > consequences. Fact of life in physics.
>
> This is bizarre! Above you use the concept of not only out of sight,
> but "out of mind".
> (regarding points off the surface of your "curved" universe).

That's right. The point that is "off" our 4D space has no physical
place in our 4D space. If it's not necessary to describe what's going
on, then why *must* it have existence?

> Here is a useful concept:
> Because frequency = wavelength x velocity when a change in f is
> noted, and the source of the wavelength is unlikely to have undergone a
> local physical/chemical change,

I don't know why you think the local physical or chemical process
"makes" wavelengths. The local process makes a disturbance there at
that local place. The propagation of that disturbance is what creates
the wavelength. It's not like the wavelength is some object extruded
from a machine. I don't know why you would think that it is.

Nice change in subject, by the way.

> the VERY HIGH likelihood is, that the
> relative velocity of the source and observer has altered.

Nope. Not at all.

> FACT, rather than MAGIC

Magic is only magic to those who don't understand what is really going
on. Ask any magician. Ask Penn and Teller.

> >

[snip]

> > > > > > Ah, that explains it. So you took the word of a physics charlatan to be
> > > > > > the truth about SR that "everyone" should know.
> > > > > >
> >
> > I already recanted that statement.
>
> Yes , and with no other explanation so it shows your inbuilt bias.
> Don't snip relevent material without indication........it is merely
> gutless.
>

I'm sorry... what relevant material was that?

PD

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