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A Physicist Who Denies That Dark Matter Exists

cosmos.nautil.us

161–170 of 193 posts

Re: A Physicist Who Denies That Dark Matter Exists

#161
post #119

Earlier quoted context omitted.

Weak attempt. The mind is what the brain does. The very same way your browser appears on your screen. Good philosophers, mostly eastern ones, tried very hard to establish a distinction between products of imagination and adequate representations of what is. The classic example is how the brain conditioned by hundreds of thousands of years by Mother Nature readily mistakes a rope for a snake. Notice, that there is not…

Don't change the subject. Explain how consciousness arises, and describe an experiment that replicates it.

Every single morning one could see how it changes the states. For proper experimental evidences visit any hospital.

Re: A Physicist Who Denies That Dark Matter Exists

#162
post #3

> "If Newtonian physics can’t predict the fixed curves, perhaps we should fix Newton, instead of making up a whole new class of matter just to fit our measurements." I've always felt this way about dark matter, but as a lay person with no background in physics, it's an opinion I'm hesitant to express. if you have a model that predicts something, but the prediction is off by several orders of magnitude, the model is w…

But isn't the problem that we have pretty-damning-but-still-not-direct evidence for dark matter?

If you choose to rather adjust Newtonian physics, we have to go all in and the new problem becomes not only how to "fix" it but also how to explain away the clumping of the Cosmic Microwave Background that is thought to be due to dark matter, the graviational lensing in the Bullet Cluster, the large-scale "web" structure of galaxies in the Universe. Structures and effects that actually fit a dark matter universe pretty well.

But yes, maybe there _is_ something else going on, and as a software developer sometimes working on the most terrible things of all: combinations of bugs interacting, and where you keep hunting down a futile rabbit hole assuming a single bug.

Maybe this is a combination of bugs in our theories interacting. It could be that this is part flaws in the Newtonian model, part about faults in some other model? That might explain why we've been bashing our heads on the dark matter wall for so long now.

Re: A Physicist Who Denies That Dark Matter Exists

#163
post #161

Earlier quoted context omitted.

Don't change the subject. Explain how consciousness arises, and describe an experiment that replicates it.

Every single morning one could see how it changes the states. For proper experimental evidences visit any hospital.

You said

  Nothing exist unless experimentally proven and replicated.
Describe the experiment that proves you are conscious.

Re: A Physicist Who Denies That Dark Matter Exists

#165
post #161

Earlier quoted context omitted.

Every single morning one could see how it changes the states. For proper experimental evidences visit any hospital.

You said Nothing exist unless experimentally proven and replicated. Describe the experiment that proves you are conscious.

I did.

Re: A Physicist Who Denies That Dark Matter Exists

#166
post #165

Earlier quoted context omitted.

You said Nothing exist unless experimentally proven and replicated. Describe the experiment that proves you are conscious.

I did.

What you subjectively experience in the morning is not proof of anything.

Since you continue to evade the question, I will only ask once more time: Describe the experiment that demonstrates the existence of consciousness in a manner which is "experimentally proven and replicated".

I'm forced to interpret failure to describe the experiment as your admission that you don't actually require "experimentally proven and replicated" to believe things, or at least that you cherry pick some propositions to require that standard.

That's OK too, no one is demanding that you be intellectually honest or self-consistent. But you should not be surprised if people call you out on it though.

Re: A Physicist Who Denies That Dark Matter Exists

#167
post #165

Earlier quoted context omitted.

I did.

What you subjectively experience in the morning is not proof of anything. Since you continue to evade the question, I will only ask once more time: Describe the experiment that demonstrates the existence of consciousness in a manner which is "experimentally proven and replicated". I'm forced to interpret failure to describe the experiment as your admission that you don't actually require "experimentally proven and re…

Oh, please, cut this cosplay out. In every surgery room of the whole world you could see how chemical compounds administered to patients would turn them unconscious and back. This implies that the consciousness is a product of the brain, not some immaterial substance, divine presence or other kind of abstract crap. This also implies that it is not mere an abstract idea of so-called pure reason ("soul", "I" and "god" are such idea, "awareness" isn't), but a valid linguistic label associated to a real high-level biological phenomena (a set of coordinated processes).

In every neurology department which deals with brain injures and pathology one could see the evidences that the states of consciousness and even its pretense or absence are bound by particular parts of the brain, which, in turn, is an artifact conditioned by the evolutionary forces and constraints of this particular universe and its physical laws.

The way medical science went from Phineas Gage to modern maps of the brain centers, insights into how the vision sub-system works, etc. constitutes the experimental proofs you are asked for.

The proof could be considered still incomplete (but nevertheless it is valid because there is not a single contradiction in what is experimentally confirmed), because there is no way to describe step-by-step the whole development from a single fertilized egg to you, but there is no doubt that there is nothing extra to that mere "mechanical" process, and that the mind is what the brain does and that conscious, which some people would call primordial awareness, is mere a product of the brain activity, which can be affected by chemical compounds and even switched on and off, which, BTW, happens every time you fall asleep (because it is not required) and wake up.

Re: A Physicist Who Denies That Dark Matter Exists

#168
post #115

Earlier quoted context omitted.

The Bullet Cluster isn’t the incontrovertible evidence for particle dark matter that you have been told it is http://backreaction.blogspot.nl/2017/01/the-bullet-cluster-a...

I wouldn't agree with that post - the probabilities and number of clusters imply we'd expect a bullet cluster. In fact, we observe other similar lower-mass systems. As an astronomer in the field of clusters, I don't know anyone who takes MOND-like theories seriously. Any non dark matter explanation for the bullet cluster would have to be extremely contrived.

  the probabilities and number of clusters imply we'd expect 
  a bullet cluster
Not according to the references in that article, which put the probability of seeing such a cluster at 10E-4 to 10E-6. And Sabine isn't one to conveniently forget to multiply that probability with the number of clusters: that's already factored in.

Re: A Physicist Who Denies That Dark Matter Exists

#169
post #167

Earlier quoted context omitted.

What you subjectively experience in the morning is not proof of anything. Since you continue to evade the question, I will only ask once more time: Describe the experiment that demonstrates the existence of consciousness in a manner which is "experimentally proven and replicated". I'm forced to interpret failure to describe the experiment as your admission that you don't actually require "experimentally proven and re…

Oh, please, cut this cosplay out. In every surgery room of the whole world you could see how chemical compounds administered to patients would turn them unconscious and back. This implies that the consciousness is a product of the brain, not some immaterial substance, divine presence or other kind of abstract crap. This also implies that it is not mere an abstract idea of so-called pure reason ("soul", "I" and "god"…

I didn't ask whether consciousness is abstract crap, nor did I ask about vision subsystems (which aren't even unique to brains), nor did I ask you to explain the whole process of development from fertilized egg to me. Well, unless that has something to do with the experiment that would show that consciousness exists, which it may or may not, at least you drew no apparent connections in your post.

I asked you to describe the experiment which proves that consciousness exists.

Merely saying that consciousness is a product of the brain is like proving dark matter by saying it's a product of the universe. I hope you can understand why that is not a convincing argument.

Re: A Physicist Who Denies That Dark Matter Exists

#170
post #115

Earlier quoted context omitted.

I wouldn't agree with that post - the probabilities and number of clusters imply we'd expect a bullet cluster. In fact, we observe other similar lower-mass systems. As an astronomer in the field of clusters, I don't know anyone who takes MOND-like theories seriously. Any non dark matter explanation for the bullet cluster would have to be extremely contrived.

the probabilities and number of clusters imply we'd expect a bullet cluster Not according to the references in that article, which put the probability of seeing such a cluster at 10E-4 to 10E-6. And Sabine isn't one to conveniently forget to multiply that probability with the number of clusters: that's already factored in.

The Thompson et al paper linked is precisely a probability for pairs of clusters, so needs to be scaled (see comments on article). There's a nice comment in the article by Peter Erwin giving an overview of a list of recent papers:

  Hayashi & White 2006 -- BC is apparently consistent with LCDM.
  Farrar & Rosen 2007 -- BC is apparently not consistent with LCDM.
  Nusser 2008 -- BC possibly not consistent with LCDM.
  Angus & McGaugh 2008 -- BC is more consistent with MOND cosmology than LCDM.
  Llinares et al. 2009 -- BC is more consistent with MOND cosmology than LCDM.
  Lee & Komatsu 2010 -- BC is apparently not consistent with LCDM.
  Forero-Romano et al. 2010 -- BC is apparently consistent with LCDM.
  Thompson & Nagamine 2012 -- BC is apparently not consistent with LCDM.
  Watson et al. 2014 -- BC is apparently consistent with LCDM.
  Krajlic & Sarkar 2015 -- BC is apparently consistent with LCDM.
  Bouillot et al. 2015 -- BC is apparently consistent with LCDM.
  Thompson et al. 2015 -- BC is apparently consistent with LCDM.
LCDM is Lambda CDM, the prevailing cosmological model. BC = Bullet Cluster. The blog post is very selective in the papers discussed.
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