Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
Dreaded Anomaly Send a noteboard - 04/05/2011 04:18:18 AM
Perhaps so, but the evidence for any one explanation (or group of explanations) still seems inconclusive.
Again, that's because you have an overly-limited view of the evidence.
An analogy to other types of known normal matter doesn't really help the cause of exotic dark matter. You're essentially listing other explanations for missing mass that require no exotic dark matter.
No, because those particles either have too little mass or are not stable, which precludes them from being dark matter candidates. The point is that particles which don't interact electromagnetically are not unknown.
Ultimately, yes, and if dark matter and/or dark energy are invalid concepts then those ardently contending they're the only possible explanations and pursuing proof of same today will be much chagrined by tomorrows scientists exposing their errors. If that's how things develop, however, I'd prefer the process take decades rather than centuries, and the more inertia an erroneous theory has within the community the more evidence it will take to overcome it.
I think the suggestion that debunking a scientific hypothesis in the modern era could take centuries is ludicrous and without any support from recent history, taking into account the major progress in science since the scientific revolution.
That's fair enough, provided we don't inadvertently allow it become an excuse for never finding direct evidence. Otherwise there's no difference between dismissing the lack of direct evidence for dark matter and dismissing the lack of direct evidence for MACHOs; it's just a question of which theory unsupported by direct evidence one prefers.
As we're only in the beginning stages of direct detection experiments for dark matter, that is not yet a scenario which merits serious concern.
I don't think it's flimsy, as such, but I do think it inconclusive.
Theoretical estimates of normal dark matter could be off.
Less of it could lie in the immediate vicinity of lensed objects but more along the complete path between us and them.
The image itself could be distorted if the lensing mass is so close it strongly affects parts of the background but others little or none.
Those are just the most obvious solutions occurring to one layman, acknowleding that all may be untenable. Regardless, the basic principle that experiments and observation should seek new theories and test existing ones rather than simply to prove existing ones remains valid. An anomaly alerted us to a problem, but just because a solution that may be tenable was found doesn't mean we should just set out to prove that solution and cease bothering to look for one that fits the evidence better, particularly if one exists that both fits the evidence better AND is simpler.
Theoretical estimates of normal dark matter could be off.
Less of it could lie in the immediate vicinity of lensed objects but more along the complete path between us and them.
The image itself could be distorted if the lensing mass is so close it strongly affects parts of the background but others little or none.
Those are just the most obvious solutions occurring to one layman, acknowleding that all may be untenable. Regardless, the basic principle that experiments and observation should seek new theories and test existing ones rather than simply to prove existing ones remains valid. An anomaly alerted us to a problem, but just because a solution that may be tenable was found doesn't mean we should just set out to prove that solution and cease bothering to look for one that fits the evidence better, particularly if one exists that both fits the evidence better AND is simpler.
An anomaly alerted us to the problem and many, many observations confirmed the problem.
Proposing solutions without having a full understanding of the situation and evidence is generally a futile exercise.
Exciting video about the universe
28/04/2011 10:14:55 AM
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I still think dark matter's just non-luminous matter without a convenient light source to reflect.
28/04/2011 10:34:21 PM
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We've just about ruled out the idea that dark matter is just non-luminous "ordinary" matter.
28/04/2011 11:44:34 PM
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I'm aware of the Bullet Cluster, though admittedly not much more than that.
29/04/2011 01:52:49 AM
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Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
29/04/2011 02:56:32 AM
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Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
30/04/2011 05:02:49 PM
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Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
30/04/2011 08:56:35 PM
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Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
02/05/2011 01:28:30 AM
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Re: I'm aware of the Bullet Cluster, though admittedly not much more than that.
04/05/2011 04:18:18 AM
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There's such a thing as knowing when you're licked, and I believe I am.
07/05/2011 02:04:53 AM
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Re: There's such a thing as knowing when you're licked, and I believe I am.
09/05/2011 11:28:48 PM
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Re: There's such a thing as knowing when you're licked, and I believe I am.
14/05/2011 05:36:45 AM
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Re: There's such a thing as knowing when you're licked, and I believe I am.
17/05/2011 02:09:40 AM
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Re: There's such a thing as knowing when you're licked, and I believe I am.
19/05/2011 04:55:21 AM
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Re: There's such a thing as knowing when you're licked, and I believe I am.
24/05/2011 09:32:27 PM
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The Pati-Salam model was the one I had in mind.
24/05/2011 10:34:04 PM
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Re: The Pati-Salam model was the one I had in mind.
24/05/2011 11:08:01 PM
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Re: The Pati-Salam model was the one I had in mind.
25/05/2011 01:27:10 AM
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Re: The Pati-Salam model was the one I had in mind.
31/05/2011 09:16:18 AM
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Apologies for the delay; internet's been spotty and I've been busy lately.
10/06/2011 12:09:04 AM
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Re: Apologies for the delay; internet's been spotty and I've been busy lately.
14/06/2011 03:38:18 AM
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Also, re: lensing from ordinary matter:
29/04/2011 05:18:47 AM
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This seems like another example of what confuses the issue.
30/04/2011 05:25:04 PM
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Re: This seems like another example of what confuses the issue.
30/04/2011 08:56:40 PM
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That discussion seems to reduce to "as little new and exotic physics as possible".
02/05/2011 01:29:03 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
04/05/2011 04:18:24 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
07/05/2011 02:05:02 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
09/05/2011 11:29:36 PM
- 831 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible".
14/05/2011 05:35:56 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
17/05/2011 02:09:55 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
19/05/2011 02:47:25 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
24/05/2011 09:46:30 PM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
25/05/2011 12:20:10 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
31/05/2011 09:16:22 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
10/06/2011 12:04:06 AM
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Re: That discussion seems to reduce to "as little new and exotic physics as possible".
14/06/2011 03:38:12 AM
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Re: I still think... (apparently, there is a 100 character limit on subjects, and yours was 99)
28/04/2011 11:57:15 PM
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Seems to happen to me a lot; sorry.
29/04/2011 12:56:14 AM
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None of this reflects on the actual facts of dark matter.
29/04/2011 01:32:52 AM
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I concede my grasp (or grope) is a somewhat superficial laymans, yes.
30/04/2011 04:30:28 PM
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Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes.
30/04/2011 08:56:44 PM
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Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes.
02/05/2011 01:28:58 AM
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Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes.
04/05/2011 04:18:27 AM
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I don't object to changing my mind, but can take more convincing than I really should.
07/05/2011 02:05:09 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
09/05/2011 11:32:17 PM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
14/05/2011 05:36:24 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
17/05/2011 02:10:03 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
19/05/2011 04:33:06 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
24/05/2011 09:59:38 PM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
24/05/2011 11:19:43 PM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
24/05/2011 11:33:58 PM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
25/05/2011 12:55:36 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
31/05/2011 09:16:24 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
10/06/2011 12:09:13 AM
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Re: I don't object to changing my mind, but can take more convincing than I really should.
14/06/2011 03:38:05 AM
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Might help if you clarified where your skepticism is at
29/04/2011 02:32:07 AM
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Potentially either, or a combination of the two.
30/04/2011 02:36:50 PM
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It's hard to discuss without knowing your objections a bit more clearly
30/04/2011 04:58:03 PM
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My primary objection is that alternatives to dark matter seem to have been ruled out prematurely.
02/05/2011 01:29:14 AM
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