Dark Matter...WTH?

[Doc_Grey]

Wow, I definately got what I asked for when I made my original post: Your opinions. It's certainly underscored the significant lack of consensus!

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, I definately got what I asked for when I made my original post: Your opinions. It's certainly underscored the significant lack of consensus! <br />Posted by Doc_Grey</DIV></p><p>But there is total consensus.&nbsp; The consensus is "we don't know" what dark matter is or if it is, but we do know that we don't see enough regular matter to account for orbits that we see.&nbsp; You will only see consensus in physics when there is a solid explanation backed by solid theory that has experimental verification.&nbsp; Without the theory and data there should not be any consensus.</p><p>If you have consensus on the answer to an unsettled (unsettled meansing that&nbsp; both&nbsp;theory and experimental data are lacking) question then there is a big problem -- it is quite likely that everyone is wrong.&nbsp; Note that "theory" does not mean "hypothesis", it means a mathematical model with predictive power that has been experimentally validated. </p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, I definately got what I asked for when I made my original post: Your opinions. It's certainly underscored the significant lack of consensus! <br />Posted by Doc_Grey</DIV></p><p>But there is total consensus.&nbsp; The consensus is "we don't know" what dark matter is or if it is, but we do know that we don't see enough regular matter to account for orbits that we see.&nbsp; You will only see consensus in physics when there is a solid explanation backed by solid theory that has experimental verification.&nbsp; Without the theory and data there should not be any consensus.</p><p>If you have consensus on the answer to an unsettled (unsettled meansing that&nbsp; both&nbsp;theory and experimental data are lacking) question then there is a big problem -- it is quite likely that everyone is wrong.&nbsp; Note that "theory" does not mean "hypothesis", it means a mathematical model with predictive power that has been experimentally validated. </p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, I definately got what I asked for when I made my original post: Your opinions. It's certainly underscored the significant lack of consensus! <br />Posted by Doc_Grey</DIV></p><p>But there is total consensus.&nbsp; The consensus is "we don't know" what dark matter is or if it is, but we do know that we don't see enough regular matter to account for orbits that we see.&nbsp; You will only see consensus in physics when there is a solid explanation backed by solid theory that has experimental verification.&nbsp; Without the theory and data there should not be any consensus.</p><p>If you have consensus on the answer to an unsettled (unsettled meansing that&nbsp; both&nbsp;theory and experimental data are lacking) question then there is a big problem -- it is quite likely that everyone is wrong.&nbsp; Note that "theory" does not mean "hypothesis", it means a mathematical model with predictive power that has been experimentally validated. </p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, I definately got what I asked for when I made my original post: Your opinions. It's certainly underscored the significant lack of consensus! <br />Posted by Doc_Grey</DIV></p><p>But there is total consensus.&nbsp; The consensus is "we don't know" what dark matter is or if it is, but we do know that we don't see enough regular matter to account for orbits that we see.&nbsp; You will only see consensus in physics when there is a solid explanation backed by solid theory that has experimental verification.&nbsp; Without the theory and data there should not be any consensus.</p><p>If you have consensus on the answer to an unsettled (unsettled meansing that&nbsp; both&nbsp;theory and experimental data are lacking) question then there is a big problem -- it is quite likely that everyone is wrong.&nbsp; Note that "theory" does not mean "hypothesis", it means a mathematical model with predictive power that has been experimentally validated. </p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[Doc_Grey]

Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. W<em>e don't know</em> is one of the few agreements in the thread.

 

[Doc_Grey]

Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. W<em>e don't know</em> is one of the few agreements in the thread.

 

[Doc_Grey]

Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. W<em>e don't know</em> is one of the few agreements in the thread.

 

[Doc_Grey]

Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. W<em>e don't know</em> is one of the few agreements in the thread.

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. We don't know is one of the few agreements in the thread. <br /> </p><p>Posted by <em>Doc_Grey</em></DIV></p><p>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</p><p>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. </p><p>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter <em>has</em> been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.</p><p>What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. We don't know is one of the few agreements in the thread. <br /> </p><p>Posted by <em>Doc_Grey</em></DIV></p><p>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</p><p>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. </p><p>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter <em>has</em> been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.</p><p>What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. We don't know is one of the few agreements in the thread. <br /> </p><p>Posted by <em>Doc_Grey</em></DIV></p><p>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</p><p>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. </p><p>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter <em>has</em> been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.</p><p>What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Lordy Doc, when you get to hectoring 'n lecturin...I already am aware of that much. We don't know is one of the few agreements in the thread. <br /> </p><p>Posted by <em>Doc_Grey</em></DIV></p><p>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</p><p>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. </p><p>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter <em>has</em> been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.</p><p>What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br />Posted by yevaud</DIV></p><p>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.html&nbsp;</p><p>&nbsp;http://chandra.harvard.edu/photo/2007/a520/</p><p>http://chandra.harvard.edu/xray_astro/dark_matter.html</p><p>I think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; In fact that is pretty much a contradiction in terms.</p><p>There are inferences from the Chandrda observations that support the existence of dark matter.&nbsp; But they are still inferences based on apparent gravitational anomalies.&nbsp; There is clearly something going on.&nbsp; We have gravitational lensing that cannot be explained with the matter tht we can see.&nbsp; Dark matter is the best available hypothesis.&nbsp; But matter that feels only gravity, not the electromagnetic force, not the strong force, not the weak force, is still a bit hard to swallow without stronger evidence, and the hyothesis is that most if not all dark matter is non-baryonic. </p><p>I am rather conservative, and until I see either solid evidence that show me not only a problem with existing models than can be explained by the dark matter hypothesis, but also clear and direct evidence that something is there that can be detected directly or a solid explanation as to what it is (not just what it is not), then I will remain skeptical that the hypothesis should be accepted as fact.&nbsp; I have no problem with dark matter as a hypothesis.&nbsp; I have no problem with accepting it as the best available hypothesis.&nbsp; But it is not proven.&nbsp; It remains a place holder in my mind.&nbsp;</p><p>I have also seen films of "Big Foot".&nbsp; I am more willing to accept dark matter, than Big Foot (particularly since the perpetrator of the hoax has come clean).&nbsp; But my point remains that a few images of things that are hard to explain, does not consititute proof for the explanations that are offered.</p><p>I am gong to a talk on dark stuff on Wednesday by a local expert.&nbsp; Maybe I will come away more convinced.&nbsp; Maybe not.&nbsp; But it will be a good talk, a free breakfast, and a wonderful way to start the day.</p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br />Posted by yevaud</DIV></p><p>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.html&nbsp;</p><p>&nbsp;http://chandra.harvard.edu/photo/2007/a520/</p><p>http://chandra.harvard.edu/xray_astro/dark_matter.html</p><p>I think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; In fact that is pretty much a contradiction in terms.</p><p>There are inferences from the Chandrda observations that support the existence of dark matter.&nbsp; But they are still inferences based on apparent gravitational anomalies.&nbsp; There is clearly something going on.&nbsp; We have gravitational lensing that cannot be explained with the matter tht we can see.&nbsp; Dark matter is the best available hypothesis.&nbsp; But matter that feels only gravity, not the electromagnetic force, not the strong force, not the weak force, is still a bit hard to swallow without stronger evidence, and the hyothesis is that most if not all dark matter is non-baryonic. </p><p>I am rather conservative, and until I see either solid evidence that show me not only a problem with existing models than can be explained by the dark matter hypothesis, but also clear and direct evidence that something is there that can be detected directly or a solid explanation as to what it is (not just what it is not), then I will remain skeptical that the hypothesis should be accepted as fact.&nbsp; I have no problem with dark matter as a hypothesis.&nbsp; I have no problem with accepting it as the best available hypothesis.&nbsp; But it is not proven.&nbsp; It remains a place holder in my mind.&nbsp;</p><p>I have also seen films of "Big Foot".&nbsp; I am more willing to accept dark matter, than Big Foot (particularly since the perpetrator of the hoax has come clean).&nbsp; But my point remains that a few images of things that are hard to explain, does not consititute proof for the explanations that are offered.</p><p>I am gong to a talk on dark stuff on Wednesday by a local expert.&nbsp; Maybe I will come away more convinced.&nbsp; Maybe not.&nbsp; But it will be a good talk, a free breakfast, and a wonderful way to start the day.</p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br />Posted by yevaud</DIV></p><p>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.html&nbsp;</p><p>&nbsp;http://chandra.harvard.edu/photo/2007/a520/</p><p>http://chandra.harvard.edu/xray_astro/dark_matter.html</p><p>I think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; In fact that is pretty much a contradiction in terms.</p><p>There are inferences from the Chandrda observations that support the existence of dark matter.&nbsp; But they are still inferences based on apparent gravitational anomalies.&nbsp; There is clearly something going on.&nbsp; We have gravitational lensing that cannot be explained with the matter tht we can see.&nbsp; Dark matter is the best available hypothesis.&nbsp; But matter that feels only gravity, not the electromagnetic force, not the strong force, not the weak force, is still a bit hard to swallow without stronger evidence, and the hyothesis is that most if not all dark matter is non-baryonic. </p><p>I am rather conservative, and until I see either solid evidence that show me not only a problem with existing models than can be explained by the dark matter hypothesis, but also clear and direct evidence that something is there that can be detected directly or a solid explanation as to what it is (not just what it is not), then I will remain skeptical that the hypothesis should be accepted as fact.&nbsp; I have no problem with dark matter as a hypothesis.&nbsp; I have no problem with accepting it as the best available hypothesis.&nbsp; But it is not proven.&nbsp; It remains a place holder in my mind.&nbsp;</p><p>I have also seen films of "Big Foot".&nbsp; I am more willing to accept dark matter, than Big Foot (particularly since the perpetrator of the hoax has come clean).&nbsp; But my point remains that a few images of things that are hard to explain, does not consititute proof for the explanations that are offered.</p><p>I am gong to a talk on dark stuff on Wednesday by a local expert.&nbsp; Maybe I will come away more convinced.&nbsp; Maybe not.&nbsp; But it will be a good talk, a free breakfast, and a wonderful way to start the day.</p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms. It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.&nbsp; However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br />Posted by yevaud</DIV></p><p>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.html&nbsp;</p><p>&nbsp;http://chandra.harvard.edu/photo/2007/a520/</p><p>http://chandra.harvard.edu/xray_astro/dark_matter.html</p><p>I think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; In fact that is pretty much a contradiction in terms.</p><p>There are inferences from the Chandrda observations that support the existence of dark matter.&nbsp; But they are still inferences based on apparent gravitational anomalies.&nbsp; There is clearly something going on.&nbsp; We have gravitational lensing that cannot be explained with the matter tht we can see.&nbsp; Dark matter is the best available hypothesis.&nbsp; But matter that feels only gravity, not the electromagnetic force, not the strong force, not the weak force, is still a bit hard to swallow without stronger evidence, and the hyothesis is that most if not all dark matter is non-baryonic. </p><p>I am rather conservative, and until I see either solid evidence that show me not only a problem with existing models than can be explained by the dark matter hypothesis, but also clear and direct evidence that something is there that can be detected directly or a solid explanation as to what it is (not just what it is not), then I will remain skeptical that the hypothesis should be accepted as fact.&nbsp; I have no problem with dark matter as a hypothesis.&nbsp; I have no problem with accepting it as the best available hypothesis.&nbsp; But it is not proven.&nbsp; It remains a place holder in my mind.&nbsp;</p><p>I have also seen films of "Big Foot".&nbsp; I am more willing to accept dark matter, than Big Foot (particularly since the perpetrator of the hoax has come clean).&nbsp; But my point remains that a few images of things that are hard to explain, does not consititute proof for the explanations that are offered.</p><p>I am gong to a talk on dark stuff on Wednesday by a local expert.&nbsp; Maybe I will come away more convinced.&nbsp; Maybe not.&nbsp; But it will be a good talk, a free breakfast, and a wonderful way to start the day.</p><p><br /><br />&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.htmlhttp://chandra.harvard.edu/photo/2007/a520/http://chandra.harvard.edu/xray_astro/dark_matter.htmlI think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; </p><p>Posted by <em>DrRocket</em></DIV></p><p>That is as good as it's going to get.&nbsp; If you are going to demand perfection, you will be disappointed each and every time, won't you?</p><p>Then again, we've imaged polar jets from what appear to be Singularities and of course will never be quite able to image the singularity itself, and <em>that's</em> accepted.&nbsp; Sometimes you have to go with the compelling indirect evidence, as in this case. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.htmlhttp://chandra.harvard.edu/photo/2007/a520/http://chandra.harvard.edu/xray_astro/dark_matter.htmlI think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; </p><p>Posted by <em>DrRocket</em></DIV></p><p>That is as good as it's going to get.&nbsp; If you are going to demand perfection, you will be disappointed each and every time, won't you?</p><p>Then again, we've imaged polar jets from what appear to be Singularities and of course will never be quite able to image the singularity itself, and <em>that's</em> accepted.&nbsp; Sometimes you have to go with the compelling indirect evidence, as in this case. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.htmlhttp://chandra.harvard.edu/photo/2007/a520/http://chandra.harvard.edu/xray_astro/dark_matter.htmlI think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; </p><p>Posted by <em>DrRocket</em></DIV></p><p>That is as good as it's going to get.&nbsp; If you are going to demand perfection, you will be disappointed each and every time, won't you?</p><p>Then again, we've imaged polar jets from what appear to be Singularities and of course will never be quite able to image the singularity itself, and <em>that's</em> accepted.&nbsp; Sometimes you have to go with the compelling indirect evidence, as in this case. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[yevaud]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>http://www.msfc.nasa.gov/news/news/releases/2002/02-264.htmlhttp://chandra.harvard.edu/photo/2007/a520/http://chandra.harvard.edu/xray_astro/dark_matter.htmlI think it is a bit of an overstatement to say that dark matter has been imaged.&nbsp; </p><p>Posted by <em>DrRocket</em></DIV></p><p>That is as good as it's going to get.&nbsp; If you are going to demand perfection, you will be disappointed each and every time, won't you?</p><p>Then again, we've imaged polar jets from what appear to be Singularities and of course will never be quite able to image the singularity itself, and <em>that's</em> accepted.&nbsp; Sometimes you have to go with the compelling indirect evidence, as in this case. </p> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</DIV></p><p>And based upon the lensing data of galaxy collisions, the 'best' theory to explain that rotational velocity *and* explain the lensing data is to suggest that there is "missing mass" in both galaxies that our technology has not yet identified.&nbsp; </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms.</DIV></p><p>Well, that seems to subjectively depend on what side of the fence you happen to find yourself on.&nbsp; From the skeptics point of view, the mainstream hasn't come close to exhasting all the "reasonable" possibilities. </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.</DIV></p><p>This is the part that is pure speculation.&nbsp; All empirically *known* forms of matter are found in periodic tables and identified subatomic particles.&nbsp; To suggest that a new *form* of matter somewhere "out there" sounds rather suspicious since no one can produce of single gram of the stuff for "testing" purpose.&nbsp;&nbsp;&nbsp; How do you "know" that any "invisible" forms of matter exist in nature? &nbsp;</p><p>IMO this "insistance" that a new form of matter is necessary to explain these observation is at best "premature", at worst, completely misguided and unrelated to emprical science.&nbsp; *IF* one of particle collider experiments comes up with evidence to support SUSY type particles, *and* they turn out to have the longevity necessary to explain such distant observations, *and* they have the "invisible properties" that you claim they do, *then* it's a valid scientific threory.&nbsp; Without the emprical evidence of these claims that a new invisible form of matter is required, there is no way to call this "emprical science".&nbsp; What we have here is an enigma without a clear answer.</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br /> Posted by yevaud</DIV></p><p>I'm going to give DrRocket credit for pointing out here that "dark matter" cannot possibly be "imaged".&nbsp; The best you might be able to claim from these image is that "missing mass" has been tentatively mapped out based on various lensing techniques and other sorts of technologies.&nbsp; You cannot use such images to suggest that "dark matter" has been imaged.&nbsp; No such thing can occur if in fact this mass is "invisible" or "dark" as astronomers claim.</p><p>The skepticism gets amplified when more and more of these presumed "properties" keep being heaped upon the theory of "dark matter", including the need for a new form of matter, an "invisiblie/dark" form of matter, a form of matter that passes through other forms of matter, has a half life, emits gamma rays, emits high energy electrons, etc.&nbsp; Pretty soon the whole concept looks like an "ad hoc" construct with many "ad hoc" "properties" that have never been demonstrated in emprical experimentation.</p><p>You have to realize how improbable it sounds to claim that this "new form of matter" is many times more abundant than the dirt in my backyard, but whole collective industry of astronomy can't produce a single gram of the stuff or verify any of the "properties" being applied to this idea in a controlled emprical test. </p><p>How do I verify that a new form of matter exists in nature?&nbsp; How do I verify it's "dark"?&nbsp; How do I verify it emits high energy electrons?&nbsp; How do I verify it emits gamma rays and has a half life?&nbsp; How do I emprically verify it passes through other forms of matter?&nbsp; How do I verify any of these ideas in real controlled emprical tests if there isn't a single gram of this stuff to play with here on Earth? </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</DIV></p><p>And based upon the lensing data of galaxy collisions, the 'best' theory to explain that rotational velocity *and* explain the lensing data is to suggest that there is "missing mass" in both galaxies that our technology has not yet identified.&nbsp; </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms.</DIV></p><p>Well, that seems to subjectively depend on what side of the fence you happen to find yourself on.&nbsp; From the skeptics point of view, the mainstream hasn't come close to exhasting all the "reasonable" possibilities. </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.</DIV></p><p>This is the part that is pure speculation.&nbsp; All empirically *known* forms of matter are found in periodic tables and identified subatomic particles.&nbsp; To suggest that a new *form* of matter somewhere "out there" sounds rather suspicious since no one can produce of single gram of the stuff for "testing" purpose.&nbsp;&nbsp;&nbsp; How do you "know" that any "invisible" forms of matter exist in nature? &nbsp;</p><p>IMO this "insistance" that a new form of matter is necessary to explain these observation is at best "premature", at worst, completely misguided and unrelated to emprical science.&nbsp; *IF* one of particle collider experiments comes up with evidence to support SUSY type particles, *and* they turn out to have the longevity necessary to explain such distant observations, *and* they have the "invisible properties" that you claim they do, *then* it's a valid scientific threory.&nbsp; Without the emprical evidence of these claims that a new invisible form of matter is required, there is no way to call this "emprical science".&nbsp; What we have here is an enigma without a clear answer.</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br /> Posted by yevaud</DIV></p><p>I'm going to give DrRocket credit for pointing out here that "dark matter" cannot possibly be "imaged".&nbsp; The best you might be able to claim from these image is that "missing mass" has been tentatively mapped out based on various lensing techniques and other sorts of technologies.&nbsp; You cannot use such images to suggest that "dark matter" has been imaged.&nbsp; No such thing can occur if in fact this mass is "invisible" or "dark" as astronomers claim.</p><p>The skepticism gets amplified when more and more of these presumed "properties" keep being heaped upon the theory of "dark matter", including the need for a new form of matter, an "invisiblie/dark" form of matter, a form of matter that passes through other forms of matter, has a half life, emits gamma rays, emits high energy electrons, etc.&nbsp; Pretty soon the whole concept looks like an "ad hoc" construct with many "ad hoc" "properties" that have never been demonstrated in emprical experimentation.</p><p>You have to realize how improbable it sounds to claim that this "new form of matter" is many times more abundant than the dirt in my backyard, but whole collective industry of astronomy can't produce a single gram of the stuff or verify any of the "properties" being applied to this idea in a controlled emprical test. </p><p>How do I verify that a new form of matter exists in nature?&nbsp; How do I verify it's "dark"?&nbsp; How do I verify it emits high energy electrons?&nbsp; How do I verify it emits gamma rays and has a half life?&nbsp; How do I emprically verify it passes through other forms of matter?&nbsp; How do I verify any of these ideas in real controlled emprical tests if there isn't a single gram of this stuff to play with here on Earth? </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</DIV></p><p>And based upon the lensing data of galaxy collisions, the 'best' theory to explain that rotational velocity *and* explain the lensing data is to suggest that there is "missing mass" in both galaxies that our technology has not yet identified.&nbsp; </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms.</DIV></p><p>Well, that seems to subjectively depend on what side of the fence you happen to find yourself on.&nbsp; From the skeptics point of view, the mainstream hasn't come close to exhasting all the "reasonable" possibilities. </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.</DIV></p><p>This is the part that is pure speculation.&nbsp; All empirically *known* forms of matter are found in periodic tables and identified subatomic particles.&nbsp; To suggest that a new *form* of matter somewhere "out there" sounds rather suspicious since no one can produce of single gram of the stuff for "testing" purpose.&nbsp;&nbsp;&nbsp; How do you "know" that any "invisible" forms of matter exist in nature? &nbsp;</p><p>IMO this "insistance" that a new form of matter is necessary to explain these observation is at best "premature", at worst, completely misguided and unrelated to emprical science.&nbsp; *IF* one of particle collider experiments comes up with evidence to support SUSY type particles, *and* they turn out to have the longevity necessary to explain such distant observations, *and* they have the "invisible properties" that you claim they do, *then* it's a valid scientific threory.&nbsp; Without the emprical evidence of these claims that a new invisible form of matter is required, there is no way to call this "emprical science".&nbsp; What we have here is an enigma without a clear answer.</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br /> Posted by yevaud</DIV></p><p>I'm going to give DrRocket credit for pointing out here that "dark matter" cannot possibly be "imaged".&nbsp; The best you might be able to claim from these image is that "missing mass" has been tentatively mapped out based on various lensing techniques and other sorts of technologies.&nbsp; You cannot use such images to suggest that "dark matter" has been imaged.&nbsp; No such thing can occur if in fact this mass is "invisible" or "dark" as astronomers claim.</p><p>The skepticism gets amplified when more and more of these presumed "properties" keep being heaped upon the theory of "dark matter", including the need for a new form of matter, an "invisiblie/dark" form of matter, a form of matter that passes through other forms of matter, has a half life, emits gamma rays, emits high energy electrons, etc.&nbsp; Pretty soon the whole concept looks like an "ad hoc" construct with many "ad hoc" "properties" that have never been demonstrated in emprical experimentation.</p><p>You have to realize how improbable it sounds to claim that this "new form of matter" is many times more abundant than the dirt in my backyard, but whole collective industry of astronomy can't produce a single gram of the stuff or verify any of the "properties" being applied to this idea in a controlled emprical test. </p><p>How do I verify that a new form of matter exists in nature?&nbsp; How do I verify it's "dark"?&nbsp; How do I verify it emits high energy electrons?&nbsp; How do I verify it emits gamma rays and has a half life?&nbsp; How do I emprically verify it passes through other forms of matter?&nbsp; How do I verify any of these ideas in real controlled emprical tests if there isn't a single gram of this stuff to play with here on Earth? </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>True, though with a caveats, of course.&nbsp; From Fritz Zwicky in the 1930s through vera Rubin in the 60s and 70s, it was plainly apparent that something with sufficient mass was causing the rotational velocities in the outer regions of observed galaxies to exceed predictions based on observations and theory.&nbsp; This much is known.</DIV></p><p>And based upon the lensing data of galaxy collisions, the 'best' theory to explain that rotational velocity *and* explain the lensing data is to suggest that there is "missing mass" in both galaxies that our technology has not yet identified.&nbsp; </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>DR mentioned Dark Matter as being a "placeholder" for a semi-solid theory and that's cogently correct.&nbsp; However it must be mentioned that when the hypothesis' are worked out, of course Astrophysicists are going to first try well-known matter and forces on for size, before moving on to more speculative realms.</DIV></p><p>Well, that seems to subjectively depend on what side of the fence you happen to find yourself on.&nbsp; From the skeptics point of view, the mainstream hasn't come close to exhasting all the "reasonable" possibilities. </p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It is fairly apparent that there are seemingly two forms of matter, one that is visible and one not so.</DIV></p><p>This is the part that is pure speculation.&nbsp; All empirically *known* forms of matter are found in periodic tables and identified subatomic particles.&nbsp; To suggest that a new *form* of matter somewhere "out there" sounds rather suspicious since no one can produce of single gram of the stuff for "testing" purpose.&nbsp;&nbsp;&nbsp; How do you "know" that any "invisible" forms of matter exist in nature? &nbsp;</p><p>IMO this "insistance" that a new form of matter is necessary to explain these observation is at best "premature", at worst, completely misguided and unrelated to emprical science.&nbsp; *IF* one of particle collider experiments comes up with evidence to support SUSY type particles, *and* they turn out to have the longevity necessary to explain such distant observations, *and* they have the "invisible properties" that you claim they do, *then* it's a valid scientific threory.&nbsp; Without the emprical evidence of these claims that a new invisible form of matter is required, there is no way to call this "emprical science".&nbsp; What we have here is an enigma without a clear answer.</p><p>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>However, Dark matter has been imaged (finally) in more/less isolation from each other via CHANDRA in 2006.&nbsp; So it's existence is now shown to be true.&nbsp; This is quite compelling, that Dark Matter does in fact exist.What is it?&nbsp; You tell me.&nbsp; I'm keeping my opinions to myself for the moment. <br /> Posted by yevaud</DIV></p><p>I'm going to give DrRocket credit for pointing out here that "dark matter" cannot possibly be "imaged".&nbsp; The best you might be able to claim from these image is that "missing mass" has been tentatively mapped out based on various lensing techniques and other sorts of technologies.&nbsp; You cannot use such images to suggest that "dark matter" has been imaged.&nbsp; No such thing can occur if in fact this mass is "invisible" or "dark" as astronomers claim.</p><p>The skepticism gets amplified when more and more of these presumed "properties" keep being heaped upon the theory of "dark matter", including the need for a new form of matter, an "invisiblie/dark" form of matter, a form of matter that passes through other forms of matter, has a half life, emits gamma rays, emits high energy electrons, etc.&nbsp; Pretty soon the whole concept looks like an "ad hoc" construct with many "ad hoc" "properties" that have never been demonstrated in emprical experimentation.</p><p>You have to realize how improbable it sounds to claim that this "new form of matter" is many times more abundant than the dirt in my backyard, but whole collective industry of astronomy can't produce a single gram of the stuff or verify any of the "properties" being applied to this idea in a controlled emprical test. </p><p>How do I verify that a new form of matter exists in nature?&nbsp; How do I verify it's "dark"?&nbsp; How do I verify it emits high energy electrons?&nbsp; How do I verify it emits gamma rays and has a half life?&nbsp; How do I emprically verify it passes through other forms of matter?&nbsp; How do I verify any of these ideas in real controlled emprical tests if there isn't a single gram of this stuff to play with here on Earth? </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>