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From: steveu on 5 Apr 2010 21:41 >On 4/5/2010 9:42 AM, steveu wrote: >>> This reminds of a case two years ago where I met a guy who claimed to >>> have a machine that created more energy out than he put in. He >>> "verified" this by 1st measuring the amount of power going into the >>> the machine. Then he measured the power out by putting a load on it. >>> Then he concluded he got more power out than he put in. The problem >>> was he needed to measure the power going it to the maching when it was >>> loaded. Once this was done, it was clearly observed that the power out >>> was less than the power in. His investors were not happy! You can >>> google "Sprain Motor" if you want to know about that particular >>> machine. >> >> He claimed to create energy out of nothing, without some profound physics >> to support it, and actually got investors? Was Sprain his name, or was it >> Barnum? >> >> Steve >> > >You'd be surprised what people can get vc money for. > >The Moller Air Car is one of my favorites. They've kept that thing >going for several decades. Worse examples abound. I don't understand that choice of example. There is nothing fundamentally stupid about the Moller Air Car. Its hard to imagine a world where millions of them roam the skys, but it doesn't transgress any obvious physical barriers. >When I worked at a large household brand name technical company I >frequently consulted for the capital investment part of the company when >they looked at startups with wireless technology. One, and this was >only about four or five years ago, was essentially a repainted version >of VPSK/VMSK, with a very clearly traceable heritage back to that >technology. > >If you're unaware, you can read about it here: > >http://www.mwrf.com/Articles/Index.cfm?ArticleID=6992&pg=1 > >or a worthwhile critique by Phil Karn: > >http://www.ka9q.net/vmsk/critique.html > >In the late nineties the company I worked for looked at VPSK and we >quickly saw it for what it was. Ten years later it popped up again with >the repainted version (and I don't remember what they were calling it >then, but they'd changed the name to take some of the stink off). I >pointed out to the people involved that this was an old scheme with >nothing behind it, etc., etc., and provided references to the history of >VPSK/VMSK. To my dismay another researcher in our lab who also >consulted to the capital investment guys thought it was a good idea for >some reason that was never adequately explained. > >Sometimes it only takes one (perhaps misguided) individual to tell the >money guys it's a good idea even when others are pointing out it stinks. > The process is kinda crazy, and some venture capitalists like risk >and crazy-sounding stuff because on the slim chance that it really is >golden they'll make a ton of money. Not all VCs are smart. The maths and physics of this is way beyond anyone but an expert. Its easy to see how tantalising a possibility this is to investors who don't grasp that provable boundaries for the performance of comms channels exist. This can, of course, work both ways. An investor who had been informed of the channel capacity theorem might have cut off all funding for MIMO work as bogus, because theory says you can't communicate that fast. Steve
From: Steve Pope on 5 Apr 2010 21:46 steveu <steveu(a)n_o_s_p_a_m.coppice.org> wrote: > An investor who had been informed of the channel capacity > theorem might have cut off all funding for MIMO work as bogus, > because theory says you can't communicate that fast. I'm not sure I'm following. The capacity of a MIMO system is equal to the sum of the capacities of its receiver chains. Steve
From: steveu on 5 Apr 2010 21:49 >Eric Jacobsen <eric.jacobsen(a)ieee.org> wrote: > >>On 4/5/2010 9:42 AM, steveu wrote: > >>> He claimed to create energy out of nothing, without some profound physics >>> to support it, and actually got investors? Was Sprain his name, or was it >>> Barnum? > >>You'd be surprised what people can get vc money for. > >Look up "Blacklight Power" (for example on Wikipedia), which is an >energy startup based on new physics. It is not physics that >has exactly been debunked, just physics that isn't proven and >is somewhat contradictory to everything we know. It is part of a series >of possibly related phenomena that might represent new energy-producing >physics -- sonoluminesence, cold fusion, fractional quantum states. They are claiming profound new physics. If they present themselves well, why shouldn't an investor be prepared to offer a least a little seed investment, to see where it leads? This is the whole basis of VC investment - get in early on things with big potential. Get a substantial percentage of the business for a small amount. Accept a massive failure rate, but get a massive return when you hit a winner. Its almost a scatter gun philosophy by its nature. There are plenty of experts who get things horribly wrong. Put yourself in the investor's position. There's nobody you can totally trust. Even experts you've known for years and respect can be seriously wrong. Its easy to laugh at these investors, but even the most rational ones have a tough time seeing through the BS. Steve
From: Eric Jacobsen on 5 Apr 2010 23:53 On 4/5/2010 6:41 PM, steveu wrote: >> On 4/5/2010 9:42 AM, steveu wrote: >>>> This reminds of a case two years ago where I met a guy who claimed to >>>> have a machine that created more energy out than he put in. He >>>> "verified" this by 1st measuring the amount of power going into the >>>> the machine. Then he measured the power out by putting a load on it. >>>> Then he concluded he got more power out than he put in. The problem >>>> was he needed to measure the power going it to the maching when it was >>>> loaded. Once this was done, it was clearly observed that the power out >>>> was less than the power in. His investors were not happy! You can >>>> google "Sprain Motor" if you want to know about that particular >>>> machine. >>> >>> He claimed to create energy out of nothing, without some profound > physics >>> to support it, and actually got investors? Was Sprain his name, or was > it >>> Barnum? >>> >>> Steve >>> >> >> You'd be surprised what people can get vc money for. >> >> The Moller Air Car is one of my favorites. They've kept that thing >> going for several decades. Worse examples abound. > > I don't understand that choice of example. There is nothing fundamentally > stupid about the Moller Air Car. Its hard to imagine a world where millions > of them roam the skys, but it doesn't transgress any obvious physical > barriers. In my observation the claim has been that these are "just around the corner" for more than a couple decades. If you look at the "prototypes" from their early days, and the tethered demos, there's been no discernible progress in all that time in my view, at least not what would have been expected given the claims. It doesn't take much analysis to show that some of the fundamental issues, like power-to-weight, are not in the ballpark. This is why there is such a thing as technical due diligence. There's a reason they haven't materialized, despite Moller (and many others) making a show. >> When I worked at a large household brand name technical company I >> frequently consulted for the capital investment part of the company when >> they looked at startups with wireless technology. One, and this was >> only about four or five years ago, was essentially a repainted version >> of VPSK/VMSK, with a very clearly traceable heritage back to that >> technology. >> >> If you're unaware, you can read about it here: >> >> http://www.mwrf.com/Articles/Index.cfm?ArticleID=6992&pg=1 >> >> or a worthwhile critique by Phil Karn: >> >> http://www.ka9q.net/vmsk/critique.html >> >> In the late nineties the company I worked for looked at VPSK and we >> quickly saw it for what it was. Ten years later it popped up again with >> the repainted version (and I don't remember what they were calling it >> then, but they'd changed the name to take some of the stink off). I >> pointed out to the people involved that this was an old scheme with >> nothing behind it, etc., etc., and provided references to the history of >> VPSK/VMSK. To my dismay another researcher in our lab who also >> consulted to the capital investment guys thought it was a good idea for >> some reason that was never adequately explained. >> >> Sometimes it only takes one (perhaps misguided) individual to tell the >> money guys it's a good idea even when others are pointing out it stinks. >> The process is kinda crazy, and some venture capitalists like risk >> and crazy-sounding stuff because on the slim chance that it really is >> golden they'll make a ton of money. Not all VCs are smart. > > The maths and physics of this is way beyond anyone but an expert. This is why many VCs hire consultants for "technical due diligence". > Its easy > to see how tantalising a possibility this is to investors who don't grasp > that provable boundaries for the performance of comms channels exist. Again, when there's a lot of money at stake it makes sense to have the claims evaluated by people expert in the field. Going in blind isn't very wise, but I suspect that's what happens in many of these cases. > This > can, of course, work both ways. An investor who had been informed of the > channel capacity theorem might have cut off all funding for MIMO work as > bogus, because theory says you can't communicate that fast. MIMO doesn't violate any theories of which I'm aware. The basic capacity formulas for single-use of memoryless channels have been characterized as such from Shannon's earliest work. Applying formulas with those restrictions to multiple use of multipath channels (with memory) could be expected to lead one to incorrect conclusions, though. -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
From: Vladimir Vassilevsky on 6 Apr 2010 01:31
steveu wrote: > If someone tells an > investor the channel capacity expression, which it quite easy to remember, > they might well (and quite reasonably) discount as bogus any claim that two > boxes can communicate faster than that. Hmm. I can still remember old time arguments that it is impossible to communicate more then 2400 bits per second over the phone line. VLV |