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What's the smallest unit of matter?


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In reply to an earlier post on Mar 9, 2012 9:50:32 PM PST
Last edited by the author on Mar 9, 2012 9:51:35 PM PST
Geek,

Haven't you claimed to be a scientist?
=============================

Physics Geek wrote:
"No, we are not. We have proven that the speed of light is consent in all frames of reference to great precision. "
http://www.amazon.com/forum/science/ref=cm_cd_et_md_pl?_encoding=UTF8&cdForum=FxZ58KVEERYS5E&cdMsgNo=84&cdPage=4&cdSort=oldest&cdThread=Tx201KYB1CVLUJR&cdMsgID=Mx1UR4RCXTO85QE#Mx1UR4RCXTO85QE

Do scientists write under anonymous names?

If you have any pride or credibility, why hide behind the screen ?

Why do not you show people your publications?

In reply to an earlier post on Mar 9, 2012 9:55:46 PM PST
Doctor Who says:
Within experimental error, we have proven that. That is the result of an experiment, not a theory. A theory explain why that is.

I thought you claimed to have studied physics in detail.

In reply to an earlier post on Mar 10, 2012 7:29:48 AM PST
DonJuan says:
"They are more aware of this than believers, who put forth beliefs as fact."

Wrong. Believers put forth their beliefs as beliefs. Read the apostles creed for an example of that. You non-believing scientists just get confused because no one has taught you these things properly.

On the other hand, the scientists love to play word games with "hypothesis" "theory" "true" "prove" "confirm" "natural" the list goes on and on. This forum is one example of that. Jerry Coyne with his "Evolution is True" book is another.

In reply to an earlier post on Mar 10, 2012 9:04:29 AM PST
barbW says:
Hi Dave,
Are you saying my electrons can extend infinitely beyond this bounded universe?

In reply to an earlier post on Mar 10, 2012 10:29:18 AM PST
Doctor Who says:
The so called "word games" are due to precise definitions of said words. Saying that you have a theory that is not falsifiable or has not withstood any kind of test is like saying something like "In the old testament, the story of Jesus according to Luke is exceptional" or "Exodus is my favorite Gospel from the new testament." Both of theses sentences are completely incorrect. Luke is not in the old testament and Exodus is not in the new testament. I could argue that "old testament" and "new testament" don't mean what you think they mean but that would be silly. Every christian religious authority agrees on the definitions as well as many non-christian authorities.

In reply to an earlier post on Mar 10, 2012 10:42:37 AM PST
Last edited by the author on Mar 10, 2012 10:51:13 AM PST
DonJuan says:
"The so called "word games" are due to precise definitions of said words."

Can you give a precise definition of "sharpness" as it relates to diffraction?

In reply to an earlier post on Mar 10, 2012 10:53:27 AM PST
Doctor Who says:
Yes. sharpness would be the property of an object such that it has an edge that is abrupt.

i.e. Not a star which has no definite edge.

In reply to an earlier post on Mar 10, 2012 11:44:00 AM PST
Werranth.... What is your evidence that the universe is bounded? Do you know something that the leading astrophysicists at NASA and 2 of the leading theoretical cosmologists are unaware of? See the direct quotes below:

At NASA's Goddard Space Flight Center website, a page entitled Imagine the Universe also attempts to address the infinity issue. In the following quote, an astrophysicist answers a well-worded question:

The Question: (Submitted March 20, 2007)... "The acceptance of Big Bang theory assumes the universe is ultimately finite and therefore measurable. But given the physical and temporal constraints that govern all our activities, the observable and measurable (empiric) universe may surely only represent a fraction of what exists across space/time. How do we know where the universe begins and ends? And therefore - how can the concept of an infinite universe (or even multiverse constructs) be ruled out?"

The Answer: "You are right that the observable universe may be a fraction of the universe. The total energy and total volume of the universe may be infinite (we do not know), but the energy density (energy per unit volume) of the universe is finite, and this is a more important quantity for our understanding.... The multiverse theory is not ruled out, but it is still in the conceptual and mathematical stage." [NASA: Infinity, 2010]

During 2002, astrophysicists Paul Steinhardt and Neil Turok tried to break from the Big Bang pack with a paper entitled A Cyclic Model of the Universe:

"The current standard model of cosmology combines the original big bang model and the inflationary scenario. Inflation, a brief period of very rapid cosmic acceleration shortly after the big bang, can explain the homogeneity and isotropy of the universe on large scales (.100 Mpc), its spatial flatness, the distribution of galaxies, and the spatial fluctuations in the cosmic microwave background. However, the standard model has some cracks. The recent discoveries of cosmic acceleration and gravitationally self-repulsive dark energy were not predicted and have no particular role in the standard model. Furthermore, the standard model does not explain the beginning of time, the initial conditions of the universe, or what will happen in the long-term future. Here, we present a cosmological model with an endless sequence of cycles of expansion and contraction. By definition, there is neither a beginning nor end of time, nor is there a need to define initial conditions. In addition, we explain the role of dark matter and generate the homogeneity, flatness, and density fluctuations without invoking inflation.... As in inflationary cosmology, the cyclic scenario can be described in terms of the evolution of a scalar field along a potential in a fourdimensional quantum field theory." [Steinhardt & Turok, 2002]

In reply to an earlier post on Mar 10, 2012 3:34:13 PM PST
Last edited by the author on Mar 10, 2012 7:15:00 PM PST
D. Colasante says:
Hi W,

W >> Are you saying my electrons can extend infinitely beyond this bounded universe?

I must consider an electron without its fields (both E and G*) not to be an electron. So, I'm saying that if we consider its fields to be part of the electron, an electron would have a size related to the time of its existence multiplied by the speed of light, c. An electron from a pair creation event this morning would have a radius of several light-hours. An electron created near the time of the theoretical Big Bang is nearly as large as the universe, minus any supraluminal spatial expansion (and allowing for any change in the value of c over time).

The few cosmological models I have encountered give space both a head start AND no speed limit as compared to light (and everything else). In that case, what happens in spacetime, stays in spacetime. [Let's set black holes a side for now.]

*The standard model would include a field, of sorts, for the Weak interaction. I abstain for the time being, until I can decide if Weak even qualifies as either a "force" or an "interaction". Weak seems quite unlike E and G, which I consider to be different aspects of one field.

In reply to an earlier post on Mar 10, 2012 4:28:24 PM PST
Last edited by the author on Mar 10, 2012 6:52:10 PM PST
DonJuan says:
Awhile back, I tried to explain the concept of generalization. At the time, I was wondering if my example was really an instance of abstraction, instead of generalization. I'm still a bit unsure whether I phrased that example correctly, but here is a link you might like to read.

http://www.emu.edu.tr/aelci/Courses/d-318/D-318-Files/plbook/absgen.htm

Anyways, I tried replacing my thumb by a bouncy ball and a razor, and I got identical results. I think for the purposes of this experiment we can assume the sun is an opaque flat disc, oriented with its surface normal to the observer (not quite, but hopefully you get the idea).

I'm still thinking about the luminosity and ghosting issues. In addition, I'm thinking about how focusing on the sun relates to focusing on the star.

There are at least 10 books on optics, available from scribd.com, for reference.

The best one is probably: Optics, 4ed - Hecht.

In reply to an earlier post on Mar 10, 2012 5:11:22 PM PST
Doctor Who says:
"I think for the purposes of this experiment we can assume the sun is an opaque flat disc, oriented with its surface normal to the observer."

No you could cannot. a bouncy ball is sold. The sun is not. In order to diffract the light must hit the edge and that interaction is what causes detraction.
In gravitational lensing there is no physical contact between the bent light and the massive object. The two effects are completely opposite. In diffraction the distant star would appear to be in the sun. In gravitational lensing the objecting appears to shift away from the massive object.

In reply to an earlier post on Mar 10, 2012 5:33:42 PM PST
Last edited by the author on Mar 10, 2012 5:36:57 PM PST
DonJuan says:
"No you could cannot. a bouncy ball is sold. The sun is not."

The important issue here is the opacity. It has a well defined boundary that is opaque inside the boundary and transparent outside the boundary. Perhaps there is a region of translucency due to partial reflection of aerosols or medium density gaseous refraction, but these are easily accounted for.

If you really can eliminate, via spectroscopic analysis (or some other method), a ghost image consistent with diffraction patterns inside the sun please let me know. For now, my thumb bends light around it.

In reply to an earlier post on Mar 10, 2012 5:58:55 PM PST
Doctor Who says:
You thumb bends light around it because it has a solid edge that the light is interacting with. Although I should point out that the light can pass through the out layers of your thumb for a bright light source like the sun.

"The important issue here is the opacity. It has a well defined boundary that is opaque inside the boundary and transparent outside the boundary."
Not a sharp boundary. Light of about 700 nm or so needs to interact with a boundary that is that well defined. The sun is most certainly not. Three further point here:
1) the light from the 1919 experiment never made contact with the sun therefore it could not interact with the sun therefore it could not possibly undergo diffraction due to the sun.
2) lets define right to be the positive x axis. x=0 is the actual position of the star. The sun is located from x=0 to some positive value. diffraction would push the light in the positive direction. The observed effect was an apparent shift in the negative direction.
3) Diffraction operates differently on different wavelengths of light. If you use white light you would smear it out into a multicolored band.

1, 2 and 3 are more than enough to to discount the possibility of diffraction causing the 1919 gravitational lensing results. There are actually many other examples of gravitational lensing that have been discovered that operate on much larger scales. The most famous would be the Einstein cross. Since the effect has been observed elsewhere and was in precise agreement with the experimental results it can be stated with great certainty that gravitational lensing is real and is accurately described by General Relativity that we can conclude that the theory is at worst an excellent approximation for non-quantum systems.

In reply to an earlier post on Mar 10, 2012 6:05:16 PM PST
Last edited by the author on Mar 10, 2012 6:07:52 PM PST
Physics Geek wrote:
"You thumb bends light around it because it has a solid edge that the light is interacting with. Although I should point out that the light can pass through the out layers of your thumb for a bright light source like the sun."
=================================================
How can anyone decipher the meaning of the above statements?

There is nothing wrong with being dyslexic, but you claim to be a scientist, a physicist, who wants others to leave physics to you.

Where did you read about "solid edge" in connection to diffraction of waves?

In reply to an earlier post on Mar 10, 2012 6:20:11 PM PST
Doctor Who says:
"How can anyone decipher the meaning of the above statements?"
They could take third grade English.

"Where did you read about "solid edge" in connection to diffraction of waves?"

I should point out that this discussion has been going on for a while. I have been using solid to differentiate between an object like the sun which has no definite edge and something like a coin that does. However if you mean where did I get the idea that light needs to interact with something here are a few sources:

l would start here: http://en.wikipedia.org/wiki/Diffraction

"Diffraction refers to various phenomena which occur when a wave encounters an obstacle."

Or you could try Physics for Scientists and Engineers with Modern, Chapters 1-46 Chapter 38

In reply to an earlier post on Mar 10, 2012 6:40:33 PM PST
Last edited by the author on Mar 10, 2012 6:41:13 PM PST
Geek,

We have been beating up the same dead horse so many time.

Your reckless grammar errors are inexcusable as it renders the discussion tasteless.

Your naive and improper citation of irrelevant references wastes every one's time.

Look how reckless your quoted explanation has come to:

Physics Geek wrote:
"Diffraction refers to various phenomena which occur when a wave encounters an obstacle."
============================================

You could not even pinpoint the nature of objects that could cause diffraction, but you quoted a dictionary entry on the definition of diffraction to lay folks.

A final note, people with scientific curiosities harbor greater respect to learning and knowledge than your paranoid craving to the undisputed crown of ignorance.

In reply to an earlier post on Mar 10, 2012 7:03:21 PM PST
Doctor Who says:
"We have been beating up the same dead horse so many time. <sic>"
You are the one who keeps bringing it up.

"Your reckless grammar errors are inexcusable as it renders the discussion tasteless."
Really? Can you find any major error in that paragraph you quoted? Other than the qualifying phrase " for a bright light source like the sun." The sentences are proper. The last phrase is actually quite common in science. It may merit parentheses but otherwise it's fine.

"Your naive and improper citation of irrelevant references wastes every one's time. "

You asked for sources. Wikipedia is not absolutely perfect but it is usually decent. Since I find it unlikely that you will purchase a $200 textbook, web sources are what you get, along with a citation of a textbook including chapter. If you have a source that explains how diffraction can occur without the wave interacting with an object please share.

"A final note, people with scientific curiosities harbor greater respect to learning and knowledge than your paranoid craving to the undisputed crown of ignorance."
a) You are the one who clings to theories that have been discarded for more than a century and insults anyone who points out this fact.
b) The topic of the 1919 experiment that confirmed general relativity is completely inconsistent with diffraction there is no harm in pointing that out. Since when does "respect to learning" involve not pointing out the inconsistencies with a statement?

In reply to an earlier post on Mar 10, 2012 7:05:17 PM PST
Last edited by the author on Mar 10, 2012 7:16:32 PM PST
DonJuan says:
"diffraction would push the light in the positive direction."

http://demonstrations.wolfram.com/FresnelDiffractionAtAnEdge/

someone even got a master's degree for

http://cardinalscholar.bsu.edu/handle/handle/180368

Instead of a disc, I should have said an annulus.

http://chestofbooks.com/crafts/scientific-american/sup3/Diffraction-Phenomena-During-Total-Solar-Eclipses.html

This is not an easy problem.

In reply to an earlier post on Mar 10, 2012 7:15:31 PM PST
Doctor Who says:
these diffraction patters are occurring inside the shadow of the moon, or put another way light is bending around the moon and appears to be coming from its surface. The light from the star observed by the astronomers in 1919 was not. Like I said before, diffraction push the light in the positive x direction toward the center of the sun while gravitational lensing push the apparent position of the star away from the center of the sun. These are completely opposite effects.

In reply to an earlier post on Mar 10, 2012 7:40:24 PM PST
Last edited by the author on Mar 10, 2012 7:47:28 PM PST
DonJuan says:
"These are completely opposite effects."

Check out the wikipedia animation of a black hole lensing a distant galaxy, on the gravitational lensing page. Or look at the how the light reflects around a riveted piece of polished metal.

In reply to an earlier post on Mar 10, 2012 7:47:07 PM PST
Physics Geek wrote:
"Since I find it unlikely that you will purchase a $200 textbook, web sources are what you get, along with a citation of a textbook including chapter. "
=====================================
Your blind, poor soul forgot that my publications and books on diffraction were published before you landed on this planet.

Physics Geek wrote:
"If you have a source that explains how diffraction can occur without the wave interacting with an object please share."
==========================================
You must be kidding.
Google would get you 4 peer-reviewed articles with my name on diffraction alone. In those articles, you could find the most authoritative references in EM wave diffraction.

In reply to an earlier post on Mar 10, 2012 7:50:22 PM PST
[Deleted by Amazon on Mar 10, 2012 9:35:24 PM PST]

In reply to an earlier post on Mar 10, 2012 7:59:19 PM PST
Doctor Who says:
*Sigh*
gravitational lensing can make an object that was behind another object appear to be off to one side and hence be visible.
diffraction causes light bands to appear inside the area that should be blocked by a line of sight. Opposite effects.

In reply to an earlier post on Mar 10, 2012 8:04:50 PM PST
Physics Geek wrote:
"And you explained how a wave can defract around an object "
===================================
Are we still writing third grade English?
Do you have a dictionary that can define "defract"? lazy bastard.

In reply to an earlier post on Mar 10, 2012 8:12:01 PM PST
Last edited by the author on Mar 10, 2012 8:13:14 PM PST
Doctor Who says:
carefull what you post:
Its missing an "f" but even you should be able to figure out it should have been:

dif·fract verb \di-ˈfrakt\
transitive verb
: to cause to undergo diffraction
See diffract defined for English-language learners »
See diffract defined for kids »
Examples of DIFFRACT

Light is diffracted when it passes through a prism.

http://www.merriam-webster.com/dictionary/diffract

Now either explain how light can diffract around an object without interacting with or go away. I don't think you will try because you know that light does not. How it has happened that you have managed to avoid being banned by amazon, I have no idea...
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Discussion in:  Science forum
Participants:  31
Total posts:  127
Initial post:  Feb 22, 2012
Latest post:  Nov 15, 2012

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