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Einstein said: Time is what the clock measure.
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AllYou!
science forum Guru


Joined: 08 May 2005
Posts: 1088

PostPosted: Wed Jul 19, 2006 11:47 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

"tomgee" <tyropress@yahoo.com> wrote in message
news:1153275755.700181.197940@i42g2000cwa.googlegroups.com...


Quote:
When opinions seem to agree, we can be content to accept
them as true unless and until we learn or come to think of
one that differs.

Then it's true that you're an idiot.


Quote:
We can seek opinions from others, but in
many cases, theirs are just copied or learned from others
without objective analysis of a valid kind.

How do you know?



Quote:
It is therefore up to
us as individuals to try to sort the real and whole truth from
those differing opinions.

And does data ever enter the picture?
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PD
science forum Guru


Joined: 03 May 2005
Posts: 4363

PostPosted: Wed Jul 19, 2006 11:38 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

tomgee wrote:
Quote:

No one should believe Encarta, nor any other reference work,
without comparison to what others say about the subject. You
believed one source that implied DM was not invisible, it is
just too dim for us to see it. Another shows DM is apparently
everywhere RM is not, so it is not a question of dimness but
of invisibility. Believe whichever one you want, but the latter
makes more sense to me, even if Encarta or any other source
said otherwise.


What's the source that "shows DM is apparently everywhere"?

PD
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Bob Cain
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Joined: 07 Jun 2005
Posts: 360

PostPosted: Wed Jul 19, 2006 8:08 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

kenseto wrote:

Quote:
If you want to talk about IRT you should read and understand IRT. In IRT the
quantity Fab is measured and if Fab is not constant a mean value is used in
the equation. In the case of the transverse doppler the mean value is at the
point where the source is directly over the observer.

Which has nothing at all to do with the point of the post you're
"responding" to. Endless evasion is your sole skill. Seto, you may
be a kook but you are also a fraudulent one. Even you must know what
your constant need to evade means.

You just do this for the fun of engaging people. Not an unusual need
and acting the fool is actually not an unusual way to fulfill it. Try
getting out more.


Bob
--

"Things should be described as simply as possible, but no simpler."

A. Einstein
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stephen@nomail.com
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Joined: 11 Sep 2005
Posts: 681

PostPosted: Wed Jul 19, 2006 5:17 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

In sci.physics.relativity stephen@nomail.com wrote:
Quote:
Note that Dirac says
"One might, therefore, be inclined to assume that electrons
in negative-energy states are just positrons, but this will
not do, because the observed positrons certainly do not
have negative energies."
Positrons are not negative-energy states because they do
not have negative energies.

That should read
Positrons are not electrons in negative-energy states because
they do not have negative energies.
Quote:
Dirac's "Dark Matter", the electrons
in negative-energy states have negative energy. Of course Dirac
never called this "Dark Matter" and as far as I know he
never really thought about the dark matter astronomers worry about.

I imagine you will jump all over that typo anyway.

Stephen
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stephen@nomail.com
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Joined: 11 Sep 2005
Posts: 681

PostPosted: Wed Jul 19, 2006 5:14 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Quote:
stephen@nomail.com wrote:
In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter
"In cosmology, dark matter refers to matter particles, of unknown
composition, that do not emit or reflect enough electromagnetic
radiation (light) to be detected directly,"
"The dark matter component has vastly more mass than the
"visible" component of the universe"

Nothing in there about +mass.

Do you honestly believe that a negative mass can be more than
a positive mass?

Why not?

Because negative numbers are smaller than positive numbers?

Quote:

The visible component of the Universe
has a positive mass.

Yes, that's what I said, precisely.

So you are right about one thing.

Quote:

The dark matter component has more
mass than the visible component. A negative number cannot
be larger than a positive number. What do you think 'more'
means?

Obviously, you miscomprehended what you read. By
"component", the article refers to the total amount of
all the DM versus all the RM. He is not talking about
individual particles of matter. He should have said,
"The total amount dark matter mass is more than that
of the +mass." You have also misunderstood what
Dirac meant by "negative mass".

Dirac has nothing to do with this. Nobody but you
thinks that dark matter has anything to do with
Dirac's virtual sea of negative energy (yes Dirac
used the term 'negative energy'). If dark matter has
negative mass, than it cannot have more mass than
the visible component of the universe.

And nobody is talking about individual particles
of matter. How could anybody talk about individual
particles of dark matter when nobody knows exactly
what dark matter is made of? The only thing
that can be determined about dark matter is its mass.
It has more mass than the visible universe. The visible
universe has a positive mass. Therefore dark matter
must also have a positive mass.

Quote:
To him, an electron goes into an extraordinary state
when it loses energy to a level below its ground state.

According to Dirac, it goes into a negative energy state.

Quote:
At that point, the electron has lost its +mass and now
has mass less than zero, which Dirac called negative
mass, as compared to mass that has positive mass.
AFAIK, he made no reference to the amount of mass
involved, nor to any state of charge.

Electrons always had negative charge according to
Dirac. Even the electrons in the negative energy states.
When you elevated an electron out of a negative energy state,
it left a hole, that acted like a positively charged particle
with the same mass as an electron. Of course none of
this is considered to be a valid model of the Universe anymore,
and it never had anything to do with Dark Matter.

By the way, here is what Dirac himself had to say about
his theories. From
nobelprize.virtual.museum/nobel_prizes/physics/laureates/1933/dirac-lecture.pdf
An examination of the behaviour of these states in an electromagnetic
field shows that they correspond to the motion of an electron
with a positive charge instead of the usual negative one - what
the experimenters now call a positron. One might, therefore,
be inclined to assume that electrons in negative-energy states
are just positrons, but this will not do, because the observed
positrons certainly do not have negative energies. We can, however,
establish a connection between electrons in negative-energy states
and positrons, in a rather more indirect way.

We make use of the exclusion principle of Pauli, according to which
there can be only one electron in any state of motion. We now make
the assumptions that in the world as we know it, nearly all the
states of negative energy for the electrons are occupied, with
just one electron in each state, and that a uniform filling of
all the negative-energy states is completely unobservable to us.
Further, any unoccupied negative-energy state, being a departure
from uniformity, is observable and is just a positron.

Note that Dirac says
"One might, therefore, be inclined to assume that electrons
in negative-energy states are just positrons, but this will
not do, because the observed positrons certainly do not
have negative energies."
Positrons are not negative-energy states because they do
not have negative energies. Dirac's "Dark Matter", the electrons
in negative-energy states have negative energy. Of course Dirac
never called this "Dark Matter" and as far as I know he
never really thought about the dark matter astronomers worry about.


Quote:
Since it involves the total loss of energy, the mass
becomes invisible.

Why? Neutrinos have mass and energy but they are
invisible. You cannot see a neutrino.

Quote:
That is because for objects to be
visible to us, they must have energy.

No, for an object to be visible to us it must be able
to interact with light, and there must be some light
with which it can interact.

Quote:
To have energy,
they must have temperature, and for that, they must
have +mass, according to E=mc^2 and the Principle
of the Conservation of Mass and Energy. Those are
the objects we can see. The DM is the negative mass
matter Dirac refers to and which I propose is the DM
of today that is invisible to us.

What you propose has nothing to do with what the
rest of the world calls dark matter. You have
already agreed that your definition of dark matter
has nothing to do with the standard definition.
Dark matter has positive mass, and dark matter
gravitates just like any other matter. That is
how the term is defined. Your definition is also at
odd's with Dirac's where electrons can have negative energy.
You insist that your dark matter cannot have negative
energy, so it cannot be the same stuff Dirac was talking
about.

Stephen
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tomgee1
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Joined: 31 Jan 2006
Posts: 750

PostPosted: Wed Jul 19, 2006 2:53 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

stephen@nomail.com wrote:
Quote:
In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter
"In cosmology, dark matter refers to matter particles, of unknown
composition, that do not emit or reflect enough electromagnetic
radiation (light) to be detected directly,"
"The dark matter component has vastly more mass than the
"visible" component of the universe"

Nothing in there about +mass.

Do you honestly believe that a negative mass can be more than
a positive mass?

Why not?

The visible component of the Universe
has a positive mass.

Yes, that's what I said, precisely.

The dark matter component has more
mass than the visible component. A negative number cannot
be larger than a positive number. What do you think 'more'
means?

Obviously, you miscomprehended what you read. By

"component", the article refers to the total amount of
all the DM versus all the RM. He is not talking about
individual particles of matter. He should have said,
"The total amount dark matter mass is more than that
of the +mass." You have also misunderstood what
Dirac meant by "negative mass".

To him, an electron goes into an extraordinary state
when it loses energy to a level below its ground state.
At that point, the electron has lost its +mass and now
has mass less than zero, which Dirac called negative
mass, as compared to mass that has positive mass.
AFAIK, he made no reference to the amount of mass
involved, nor to any state of charge.

Since it involves the total loss of energy, the mass
becomes invisible. That is because for objects to be
visible to us, they must have energy. To have energy,
they must have temperature, and for that, they must
have +mass, according to E=mc^2 and the Principle
of the Conservation of Mass and Energy. Those are
the objects we can see. The DM is the negative mass
matter Dirac refers to and which I propose is the DM
of today that is invisible to us.
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tomgee1
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Joined: 31 Jan 2006
Posts: 750

PostPosted: Wed Jul 19, 2006 2:22 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

stephen@nomail.com wrote:
Quote:
In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter

Wiki-wiki? You're using wiki-wiki the editable-by-anyone online
website for unsupported opinions? Even now that Encarta is free
online? What kind of simpleton would prefer to use a source that
he does not have to use and that any fool can edit and say
whatever he wants to in it?

Two things. First, Encarta is not free online. Parts of it are,
but if you want to see all the articles, you have to pay for
them. For example, one article you have to pay to see is
http://encarta.msn.com/encyclopedia_761579459/Dark_Matter.html
So either you are misinformed, or you lied about the Encarta being
free. Second, according to you "Encarta leaves out a few important facts"
and "throws in a some opinions as facts." So why should anyone
believe Encarta? You apparently do not. So why recommend an
inaccurate source of information for which you have to pay?

No one should believe Encarta, nor any other reference work,

without comparison to what others say about the subject. You
believed one source that implied DM was not invisible, it is
just too dim for us to see it. Another shows DM is apparently
everywhere RM is not, so it is not a question of dimness but
of invisibility. Believe whichever one you want, but the latter
makes more sense to me, even if Encarta or any other source
said otherwise.

For you to depend on the truth coming from others is a gamble
everytime. You can only believe that they hold certain opinions
and that those can differ based on the capacity of their owners
to better analyze that from which they formed their opinions. I
think that differing opinions about any issue or topic shows that
both cannot be correct, usually, so one of them is probably
wrong and hopefully the other is correct. They could both be
wrong, of course.

When opinions seem to agree, we can be content to accept
them as true unless and until we learn or come to think of
one that differs. We can seek opinions from others, but in
many cases, theirs are just copied or learned from others
without objective analysis of a valid kind. It is therefore up to
us as individuals to try to sort the real and whole truth from
those differing opinions. To do otherwise puts us in danger
of believing in or accepting wrong opinions, because, after
all, a reference is support for an opinion, but it is often just
another opinion.
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stephen@nomail.com
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Joined: 11 Sep 2005
Posts: 681

PostPosted: Wed Jul 19, 2006 12:54 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Quote:
Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter
"In cosmology, dark matter refers to matter particles, of unknown
composition, that do not emit or reflect enough electromagnetic
radiation (light) to be detected directly,"
"The dark matter component has vastly more mass than the
"visible" component of the universe"

Nothing in there about +mass.

Do you honestly believe that a negative mass can be more than
a positive mass? The visible component of the Universe
has a positive mass. The dark matter component has more
mass than the visible component. A negative number cannot
be larger than a positive number. What do you think 'more'
means?

Stephen
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tomgee1
science forum Guru


Joined: 31 Jan 2006
Posts: 750

PostPosted: Wed Jul 19, 2006 12:18 am    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

Randy Poe wrote:
Quote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter
"In cosmology, dark matter refers to matter particles, of unknown
composition, that do not emit or reflect enough electromagnetic
radiation (light) to be detected directly,"
"The dark matter component has vastly more mass than the
"visible" component of the universe"

Nothing in there about +mass.

Nobody is saying it doesn't reflect any light. Merely that it doesn't
reflect enough light to be seen by our telescopes.

I think you're wrong about that, and those who think the same

are wrong too, IMO. You have to learn to write like a physicist
if you're going to argue like one. The author did not say what
you claim he said. He left out telescopes, leaving his statement
ambiguous enough to be able to escape from it if he has to.
Quote:

We can't see any brown dwarfs either.

So what? We don't see the other side of the moon either,

unless we go there. You would see a brown dwarf if you
came close enough, but DM is all around us, and still no
one can see it.
Quote:

http://astro.berkeley.edu/~mwhite/darkmatter/dm.html
"When such velocity measurements are done on large scales, it turns out
that the amount of inferred mass is much more than can be explained by
the luminous stuff. Hence we infer that there is dark matter in the
Universe."

Nothing in there about +mass either.

http://csep10.phys.utk.edu/astr162/lect/cosmology/darkmatter.html
"On smaller scales such as galaxies and clusters of galaxies, dynamical
estimates of the mass based on rotation curves or velocity dispersions
of galaxies indicate that 90% (not 99%) of the total mass is not seen
("sub-luminous").

That's incorrect, isn't it? The total real mass is about 10

percent of the closure density, and the DM mass is more
like 23-25 percent, and if we add the energy content of
such mass, the total is raised to 90-99 percent, depending
on which article one reads.
Quote:

This implies that the mass density of the Universe is
10% of the closure density. In this case, the sub-luminous mass could
be normal (baryonic) and be locked up in stellar remnants (white
dwarfs, neutron stars, black holes) or just in very dim stars called
"Brown Dwarfs"."

Nothing in there about +mass, either.


Note that it says it _could be_, and not that it is. You repeat
that as if it were a fact and not just a guess.
Quote:

Plenty more stuff out there. Search for "dark matter" and pull up
any article on an EDU site, written by an astronomer. You will find
the same basic statements: that something like 90% of the MASS
of the universe is thought to be dark, that "dark matter" is the name
given to this MASS we can't see.

Nothing in there about +mass, either. I don't disagree with

anything in there either, for that matter.
Quote:

Note the list of candidates at the end of that last quote: white
dwarfs, neutron stars, black holes, brown dwarfs.

You note that "candidates" does not mean incumbents, yet

you talk as if they are not just possible explanations for DM,
but as if they are in fact accepted explanations for DM.
Quote:

Then show us how we can see through matter
that has +mass and +energy.

Who says we can see through it? Where are you getting this requirement
from?

From the recent article reporting that some mapping of DM
has been achieved. Find it and read it.

Are you thinking that if it was opaque, we'd see a dark place in
the sky? The stuff we can see has gaps between it, you know. Look
at a picture of stars. Points of light, separated by black.

But you cannot see through those points of light, can you?

Therefore, they are not the same as DM.
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tomgee1
science forum Guru


Joined: 31 Jan 2006
Posts: 750

PostPosted: Tue Jul 18, 2006 11:50 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

Randy Poe wrote:
Quote:
tomgee wrote:
Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter

Wiki-wiki? You're using wiki-wiki the editable-by-anyone online
website for unsupported opinions?

As the first of several links. Did you miss the others?

Even now that Encarta is free
online? What kind of simpleton would prefer to use a source that
he does not have to use and that any fool can edit and say
whatever he wants to in it?

Did you miss the others, the ones from professional astronomers'
websites?

If you read them, did you see any discrepancy between the Wiki
article and the astronomers' articles?

I'm just giving you back the grief you gave me when I first began

telling you I use Encarta as a resource. As a matter of fact, I do
not prefer one over any other, because I don't go by names of
authors or scientists, but of the content in review. I criticize the
work of AE and of Encarta without blinking an eye because they
make errors just like me and you.

You don't like the grief? Good, neither did I. Did you learn not
to do that anymore? Time will tell, but I seriously doubt that you
did.
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tomgee1
science forum Guru


Joined: 31 Jan 2006
Posts: 750

PostPosted: Tue Jul 18, 2006 11:49 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

Randy Poe wrote:
Quote:
tomgee wrote:
Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter

Wiki-wiki? You're using wiki-wiki the editable-by-anyone online
website for unsupported opinions?

As the first of several links. Did you miss the others?

Even now that Encarta is free
online? What kind of simpleton would prefer to use a source that
he does not have to use and that any fool can edit and say
whatever he wants to in it?

Did you miss the others, the ones from professional astronomers'
websites?

If you read them, did you see any discrepancy between the Wiki
article and the astronomers' articles?

I'm just giving you back the grief you gave me when I first began

telling you I use Encarta as a resource. As a matter of fact, I do
not prefer one over any other, because I don't go by names of
authors or scientists, but of the content in review. I criticize the
work of AE and of Encarta without blinking an eye because they
make errors just like me and you.

You don't like the grief? Good, neither did I. Did you learn not
to do that anymore? Time will tell, but I seriously that you did.
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Randy Poe
science forum Guru


Joined: 24 Mar 2005
Posts: 2485

PostPosted: Tue Jul 18, 2006 4:43 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

tomgee wrote:
Quote:
We can't see the other side of the moon from here either,
so what? And the Stooge above said nothing about
telescopes - you just added that in to show us you are
still misinterpreting what you read.

When astronomers say they haven't seen objects corresponding
to this mass, what is it you think that astronomers use to see things?

I'm curious. What else do you think that the astronomers would
use to see matter in the universe, other than telescopes?

You are aware that the word "telescope" is used for X-ray,
gamma-ray, UV and IR instruments, right?

- Randy
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kenseto
science forum Guru


Joined: 08 May 2005
Posts: 2151

PostPosted: Tue Jul 18, 2006 3:12 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

"Bob Cain" <arcane@arcanemethods.com> wrote in message
news:8J-dnRvf9rpweCbZnZ2dnUVZ_q-dnZ2d@giganews.com...
Quote:
kenseto wrote:
"Bob Cain" <arcane@arcanemethods.com> wrote in message

Take a clock that has time t between ticks when I hold it in my hand.
Define t' as the time I measure between ticks when that clock is
moving at velocity v with respect to me. Describe a physical setup
and the equation f which gives t'=f(t,v,c) such that t'<t. What's the
equation for f in the given variables? Not a word like gamma or
mxztplk, but an equation only in t,v and c. It must yield a t'<t to
satisfy your claim.

Sigh......
t'=t/gamma
where gamma=1/(1-v^2/c^2)^1/2

Using the definitions above for t and t' I think you meant t'=t*gamma.
Right? What you wrote is true for transformation of frequency, not
period, so let's work with frequency instead of time.

f'=f/gamma

BTW, that expression obtains only at the moment when the moving
clock's velocity is entirely transverse to you, i.e. the moment when
the component of the clock's velocity toward or away from you is zero.
Otherwise there is a non-relativistic Doppler correction term as well
(due simply to the fact that light has a propegation velocity) which
can make the relative magnitudes of f' and f arbitrary in the general
case. But for the case you are trying to make, that f' can be greater
than f, we can choose _any_ point in time to be the time we take the
measurement.

But let's see where that takes us because in an inertial universe
every object moving with respect to you will have had or will have the
moment where f'=f/gamma describes the situation.

To have a f' > f at that moment (observed frequency is shifted up)
requires

gamma < 1

Substituting the definition of gamma

1/(1-v^2/c^2)^1/2 < 1

Multiplying by (1-v^2/c^2)^1/2

1 < (1 - v^2/c^2)^1/2

Squaring

1 < 1 - v^2/c^2

Subtracting 1

0 < - v^2/c^2

Adding v^2/c^2

v^2/c^2 < 0

Multiplying by c^2

v^2 < 0

Oops. That could only be true if v is imaginary and we are working
with real physical measurements.

We see that f' > f leads to a contradiction and thus can't happen.
This leaves only the possibility that f' <= f. Any moving clock
appears to run slow at the moment its motion is transverse to you
(perpendicular to the line between you and the moving clock.)

Is that consistent with your theory? Do you agree that, regardless of
which object you park yourself on, the observed rate of time passage
in any object moving with respect to you is less than yours _if_ we
subtract out the common Doppler effect due to light having a
propagation velocity (or, equivalently, choose the time the Doppler
effect is zero to do the measurement)?

If you want to talk about IRT you should read and understand IRT. In IRT the
quantity Fab is measured and if Fab is not constant a mean value is used in
the equation. In the case of the transverse doppler the mean value is at the
point where the source is directly over the observer.

Ken Seto
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stephen@nomail.com
science forum Guru


Joined: 11 Sep 2005
Posts: 681

PostPosted: Tue Jul 18, 2006 3:10 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

In sci.physics.relativity tomgee <tyropress@yahoo.com> wrote:

Quote:
Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter

Wiki-wiki? You're using wiki-wiki the editable-by-anyone online
website for unsupported opinions? Even now that Encarta is free
online? What kind of simpleton would prefer to use a source that
he does not have to use and that any fool can edit and say
whatever he wants to in it?

Two things. First, Encarta is not free online. Parts of it are,
but if you want to see all the articles, you have to pay for
them. For example, one article you have to pay to see is
http://encarta.msn.com/encyclopedia_761579459/Dark_Matter.html
So either you are misinformed, or you lied about the Encarta being
free. Second, according to you "Encarta leaves out a few important facts"
and "throws in a some opinions as facts." So why should anyone
believe Encarta? You apparently do not. So why recommend an
inaccurate source of information for which you have to pay?

Stephen
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Randy Poe
science forum Guru


Joined: 24 Mar 2005
Posts: 2485

PostPosted: Tue Jul 18, 2006 2:47 pm    Post subject: Re: Einstein said: Time is what the clock measure. Reply with quote

tomgee wrote:
Quote:
Randy Poe wrote:
tomgee wrote:
stephen@nomail.com wrote:

The
whole idea behind dark matter is that it is massive,
and it attracts other objects via gravity. That is the
definition of "dark matter". No one is assuming that
dark matter is massless, other than you. That is
the point I have been repeatedly trying to make. Nobody
thinks that dark matter has zero or negative mass. It
is in fact defined to have positive mass.

You're making up facts, now, aren't you? If not, show us
that fact you claim exists where DM is defined to have
+mass.

http://en.wikipedia.org/wiki/Dark_matter

Wiki-wiki? You're using wiki-wiki the editable-by-anyone online
website for unsupported opinions?

As the first of several links. Did you miss the others?

Quote:
Even now that Encarta is free
online? What kind of simpleton would prefer to use a source that
he does not have to use and that any fool can edit and say
whatever he wants to in it?

Did you miss the others, the ones from professional astronomers'
websites?

If you read them, did you see any discrepancy between the Wiki
article and the astronomers' articles?

- Randy
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