Do you believe in Magic?

03-20-12: Nonoise
Fascinating.

I always thought that it was a theory but as long ago as 1919 there was proof that light does bend due to strong gravitational forces.

Since Eddington's initial discovery, the study of light deflection - what is now called Gravitational Lensing - has led to some remarkable discoveries, such as Einstein Rings, which you can see a picture of here.

Gravitational Lensing techniques are also used in a variety of other astronomical research, including the detection of extrasolar planets.

Science is amazing.

Bryon

hi geoffkait:

my advice to you is to keep quiet and ignore further challenges to your products.

I thank Audiogon for allowing my last post. Although I agree with Ted Denney of Synergistic Research that it is best just to ignore insulters I think there comes a time when being frank when faced with this kind of situation -- while remaining polite and respectful -- serves a constructive purpose.

We are here to exchange opinions. If we cannot be polite and respectful then the level of discussion will deteriorate and some posters will just back off. This does not encourage the kind of participation that many of us appreciate. Full participation should always be encouraged. But when gratuitous insults are routinely allowed to stand the discussion often degrades as a result.

There are ways to let people know you do not like their opinions or their attitude without using clearly insulting language. I feel that Audiogon should have guidelines that delineate where to draw the line in order to keep worthwhile discussions active. Once a discussion degrades because of lack of civility or lack of respect it often deteriorates beyond reprieve. And that is a pity, IMO.

It is like a boxing match. If there is a low blow then that poster should be given fair warning -- publicly. If the other side replies in kind they should be given fair warning -- publicly. If there is a third infraction by either side that poster should be disallowed for the duration of the string. In this way, I believe that these strings will become self-policing and there will be far fewer instances of this occurring. This is meant as a constructive suggestion for how to manage troublesome threads.

Of course, the point of bringing up Einstein rings is that a supermassive object or group of objects is located between the viewer and the object(s) visible due to gravitational lensing. This object or group of objects can be a galaxy, supermassive black hole, or group of galaxies or black holes. But not a star. How massive is a supermassive black hole? Answer at 11.

For more details on what produces gravitational lensing you need look no further than Wikipedia.

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

03-20-12: Geoffkait
Of course, the point of bringing up Einstein rings is that a supermassive object or group of objects is located between the viewer and the object(s) visible due to gravitational lensing. This object or group of objects can be a galaxy, supermassive black hole, or group of galaxies or black holes. But not a star...

For more details on what produces gravitational lensing you need look no further than Wikipedia.

You are quite correct, a person need look no further than Wikipedia…

Gravitational microlensing is an astronomical phenomenon due to the gravitational lens effect…

Microlensing is caused by the same physical effect as strong lensing and weak lensing, but it is studied using very different observational techniques. In strong and weak lensing, the mass of the lens is large enough (mass of a galaxy or a galaxy cluster) that the displacement of light by the lens can be resolved with a high resolution telescope such as theHubble Space Telescope. With microlensing, the lens mass is too low (MASS OF A PLANET OR A STAR) for the displacement of light to be observed easily, but the apparent brightening of the source may still be detected…

Gravitational lensing was first observed in 1979, in the form of a quasar lensed by a foreground galaxy. That same year Kyongae Chang and Sjur Refsdal showed that INDIVIDUAL STARS in the lens galaxy could act as smaller lenses within the main lens… [emphasis added]

That is from Wiki’s article on microlensing, a form of Gravitational Lensing in which the lens can be as small as a single star, or even a planet.

So next time, Geoff, I suggest you take your own advice and actually READ the Wiki article.

But all of this is a ridiculously irrelevant tangent. The subject of Gravitational Lensing only came up in the context of discussing the features of good explanations, one of which is that they entail predictions. The bending of light around objects of sufficient mass, which is now referred to by the general term ‘Gravitational Lensing,’ was simply an illustration of a prediction entailed by a good explanation (General Relativity). The details of Gravitational Lensing are utterly irrelevant to the point I was making. The point I was making is this...

Of the common features of good explanations – conforming to a recognized Model of Explanation, a causal connection between explanandum and explanans, a large Circle of Justification, entailed predictions, parsimony, independent corroboration – your explanations for Machina Dynamica products do not have a SINGLE one.

But I suspect you know the point I was making, and rather than struggle to respond to it, you try to misdirect the conversation with a triviality and irrelevance. That is another act of Obscurantism.

Thank you, Geoff, for continuing to make my point.

A short while ago you said...

If we default to the most skeptical opinions, those with the narrowest definition of the "finite bounds of plausibility," how will that affect progress in many fields of human endeavor? Will we harken back to the dark ages when folks were persecuted for beliefs or abilities that lay outside the norm?

I find that comment ironic, in light of your ceaseless Obscurantism. In the Dark Ages, the powerful withheld knowledge and higher learning from the powerless largely through the use of Obscurantism.

The only person harkening back to the Dark Ages is you.

Bryon