Question to self: why is it always the same ones who can hear differences in fuses, differences in directionality or differences in cables but can never seem to demonstrate it blind therefore validating their ears? š¬
Ethernet Cables, do they make a difference?
I stream music via TIDAL and the only cable in my system that is not an "Audiophile" cable is the one going from my Gateway to my PC, it is a CAT6 cable. Question is, do "Audiophile" Ethernet cables make any difference/ improvement in sound quality?
Any and all feedback is most appreciated, especially if you noted improvements in your streaming audio SQ with a High-End Ethernet cable.
Thanks!
grm
Any and all feedback is most appreciated, especially if you noted improvements in your streaming audio SQ with a High-End Ethernet cable.
Thanks!
grm
441 responses Add your response
kosst_amojan
The facts don't allow for any choice in the matter. By definition, if you're choosing to believe in the differences of Ethernet cables, you're willfully delusional.Such a statement is an idiosyncratic belief or impression that you firmly maintain despite being contradicted by many here. That suggests that if anyone here is delusional, it's you. You might want to take a look in the mirror. |
Michters single barrel bourbon? Whoa! Sorry, Charlie! We want tuna that tastes good, not tuna with good taste. I'll bet you know a good Bourbon same as you know when a cable sounds good. By looking at the label as you drink it. Michters is the Bourbon that Pappy Van Winkle noted to get if you can't get theirs. |
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acepilot71 Ethernet cable is digital. As such it cannot change the quality of the music. >>>>Sorry, thatās the same illogical argument naysayers have been using for years to try to explain why there can be no differences between digital cables, the ones that connect to the external DAC - because itās digital. The problem with that illogical argument isĀ all signals - analog OR digital - are electromagnetic waves. As such they are subject to the same cable characteristics as any other cable - geometry, conductor material/purity, dielectric material, directionality, etc. |
Benzman 4-25-2018That seems to be a perennial question in debates such as this. And often parties on both sides of such debates tend to impute a variety of nefarious motivations to those on the other side. My own belief on this question, which I havenāt previously stated, is as follows: I believe that the great majority of those on both sides of such debates are sincere in their beliefs and in their statements. What I believe is usually the motivation of the so-called naysayers can be illustrated with a hypothetical situation: Letās say that in a music forum various classical music buffs were discussing the music of Johann Sebastian Bach. And letās say that someone submitted a post asserting in no uncertain terms that Bach was a third rate hack as a composer. Certainly the other participants would feel a natural urge to set the record straight. And it is my belief that so-called naysayers believe, rightly or wrongly (and perhaps in many situations the truth is sufficiently nuanced to lie somewhere in between), that what is being asserted by those on the other side of debates such as this is comparably ridiculous, as well as impossible. And consequently I believe their motivation in such situations is likely to be similar to that of the Bach connoisseurs in the hypothetical situation I described. Regards, -- Al |
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@burgh heavy shielding in industrial environment has many reasons (as you well aware of), standards, codes, safety... you name it. BesidesĀ Profinet, CanBus or any serial bus protocols are considered real time and delivery of each individual message in time is critical so they are mostly shielded from outside world. In Audio world at home we are free to do whatever we like, especially in lo voltage circuits - so experimental lab is open for suggestions. |
Ethernet cable is digital. As such it cannot change the quality of the music. There are very few bytes to deliver over the cable. Network protocols like TCP/IP or whichever one you use take care of the data continuity so the song file on the remote storage is identical to the file delivered to the media player and DAC. The sequence of the bytes is the same - guaranteed. It will be delivered ahead of the time when it will be played by media player and processed by the DAC since the speed and throughput of the cheapest cable exceeds the needs of the delivery channel. Media player will take care of the buffering of the data when data packets coming out of theĀ Ethernet cable into the network card and put back together into the continuous stream of bytes. Quality of the music depends on the components in the chain starting from DAC all the way to the speakers and the room, furniture in it and so on - the analog components so to say. However Ethernet cable may impact the quality of the sound, introduce noises of all kinds. That highly depends on the design of each individual system. "highly flawed system" may be one which is not shielded properly and not shielded Ethernet cable will create all kind ofĀ parasite noises. What may look and sound like " highly resolving system" may be easily brought out of balance by poorly manufacturedĀ Ethernet cable. Most likely it will not but there is a chance. Reports of improvements with high quality cables just prove that. The case when placebo affect takes place has all rights for existence: What looks good and has a significant price tag must sound good. This debate will never end due to the high permutation of the components and configurations in your systems. Too many variables in this equation. But go out there, try, experiment and improve, If you like the sound - keep the cable, if not - take it back and as for a refund :-) |
clearthink kosst_amojan"Foggythink, a highly resolving system does reveal the differences in Ethernet cables. A highly flawed system does." Costco while I completely agree that a highly resolving Music Reproduction System can reveal genuine audible differences in ethernet cables that can be reliably detected in a proper scientific double-blind listening tests I think it less likely to be detectable in what you call here a "highly flawed system." That is not to say that it will never be detectable in your hypothetical "highly flawed system" but statistically I think it is substantially less likely to be reliably detected in such a Music Reproduction System it would depend on the specific system and what exact limitations it possesses that caused it to be "highly flawed" e.g where care the non-linearities noise distortion or other flawed aspects of itās audible presentation? >>>>Iām glad someone decoded costcoās post. My code breaking machine must be broken. Shouldnāt there be a ānotā in there somewhere? Was he laying a trap?Ā |
I don't understand why folks that choose not to believe in differences in cabling actually debate with those of us that can detect differences in sound quality. I have come up with a few clues: They are all contrarians. Whether religion or politics, abortion etc. they will always take the opposite side and will back it with solid evidence( in their view)Ā to spin their agenda. Beats arguing with the wife. May not have the most resolving system: If you certainly can not hear the difference between cabling you are not going to have much better than Lampcord and BJC for interconnects. Certainly nothing wrong with that as leaves more money for upgraded golf clubs and bowling balls, upgraded rooms on vacations etc. Do not know how to listen for improvements in sound: Takes a few years as you are moving up the chain to identify small increments in improvement such as swapping out a receptacle, or the use of vibration control ,room treatments etc. As we all know a few percent here and there ends big in the long run. All measurements sound the same:Ā Ok if two Speakers measure 30hz-20kh +-2 db do they sound the same? Of course not.Ā Neither does and amp, preamp etc. Putting to together a system is all about synergy. What may work in my system may be to laid back in yours etc. I just don't understand why the non believers just don't say:"Wow that's great for you guys. I am spending time enjoying my system and less time constantly tweaking". Heck some of the best times enjoying music is have a few beers in the garage with your buds listening toĀ music played on a boombox. Seems the whole world is in an argument. This hobby is a selfish as it gets. It would be nice just to enjoy with people with like interests. I really do not see any other forums ( auto, financial, sports)with the type ofĀ bashing that goes on in audio forms.Ā Axpona was great this year. How many non believers where there?Ā Not many I am sure.Ā Sure a lot of the products are over the top, but it all trickles down over time.Ā 4 years ago at Axpona Ā Ric Shultz was showing off his magnetic cable line. We looked at each other and said WTF?Ā High Fidelity cables had 3 connected rooms this year this year to go along with two beautiful gals that knew what they were talking about!!.Ā A new affordable cable with similar qualities as a cable twice the price a few years prior. Something is working there. All sorts of great success stories all over. People that have succeeded at their passion. How awesome. I am sure not going to take anything away from them. I am a little jealous. Can we talk about cable break in now? :)Ā Ā |
kosst_amojan"Foggythink, a highly resolving system does reveal the differences in Ethernet cables. A highly flawed system does." Costco while I completely agree that a highly resolving Music Reproduction System can reveal genuine audible differences in ethernet cables that can be reliably detected in a proper scientific double-blind listening tests I think it less likely to be detectable in what you call here a "highly flawed system." That is not to say that it will never be detectable in your hypotheticalĀ "highly flawed system" but statistically I think it is substantially less likely to be reliably detected in such aĀ Music Reproduction System it would depend on the specific system and what exact limitations it possesses that caused it to be "highly flawed" e.g where care the non-linearities noise distortion or other flawed aspects of it's audible presentation? |
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Of course when you are able to get people "jacked up" on hard liquor it is very possible What? Jacked up on liquor? It was a host gift. No one was jacked up on anything. If four shots total were poured for the entire day I would have been surprised. I simply wanted to bring William something that he couldnāt get elsewhere. Michters is really good bourbon that is not readily available just anywhere. |
jinjuku"I've also offered to do this at a show. The underlying theme is people and their beliefs are easily separated.": Of course when you are able to get people "jacked up" on hard liquor it is very possible to manipulate them in to what ever belief you want them to embrace perhaps you should be completely candid with this group and tell it's many participants why you have this enduring interest in manipulating outcomes are you a manufacturer or manufacturers rep, promoter or investor attempting to achieve a specific outcome? |
jinjuku"Ā We all had a good time and food for thought. Even brought a bottle of Michters' single barrel Bourbon...People will often take something trivial and make as big of a deal of it as suites their agenda" Well of course you are free to apply your acquired standards to the reported experience of others and conclude they are "trivial" but it is up to each individual audiophile to decide for thereselves weather such difference's are trivial or represent to them a more significant contribution to the resultant performance of a Music Reproduction System and to the best of my substantial understanding of the human auditory process, system and mechanism there is no evidence at all to support the assertion that the consumption of alcoholic products of any type can in any way enhance the hearing acuity of a listener. |
Bottom line is I went out to Williamsā house. We all had a good time and food for thought. Even brought a bottle of Michters' single barrel Bourbon. He didnāt know that Tidal would cache the entire song and you could pull the plug. People will often take something trivial and make as big of a deal of it as suites their agenda. Nothing I, nor anyone else, can do about that. At that point itās the agenda speaking and not anything else. |
benzman...Pretty easy to hear the improvement. So the answer is if you have a very resolving system an upgraded Ethernet cable will definitely help. Ā Just proved it in my system. Yes this can happen and of course there are numerous other comparable testimonials already posted on this forum from other experienced contributors who have personally experienced substantially similar results and I completely agree that a significantly resolving Music Reproduction System is often a prerequisite for achieving results such as you posted. It is most unfortunate however that you will likely encounter responses to your shared experience from others who lack such experience but who have personally concluded based on the "scientific" study of white papers, printed specifications and/or basic textbook theory that such results are impossible except in cases of mental illness such as delusions or hallucinations or otherwise "placebo" affect or "sighted bias" and in fact one such deep thinker has suggested psychiatric medication to "alleviate" such delusions and other admitted that he suffers brain damage from his passed history of drug use but he still thinks listeners with sharp auditory acuity such as yourself are deluded. My efforts to demonstrate this in a public scientific blind listening test did not end well and I was specifically instructed by a Moderator to not provide the person promoting the test with any of the personal information he insisted upon me providing to him personally! |
I am referring to timing jitter at the point of D/A conversion. And I am referring to the possibility that cable differences may affect the characteristics of RF noise that may bypass (i.e., find its way **around**) the ethernet interface, buffers, etc. and **to** the circuitry that performs D/A conversion. At best thatās a design issue of the connected hardware. Not a cabling issue, IMO, where the cable meets or exceeds spec. The reason behind my thinking is that RF noise generated, by say impedance mismatch in a cable, is due more to length and twisted pairs not staying in mechanical balance than differences in 12-15 foot typical patch cable. Not to mention the horizontal run is most likely some junk CCA. At worst, and if we take your interpretation, I would say from what Iāve seen, most of the incredibly expensive CATX cabling doesnāt pass IEEE / TIA spec and it introduces noise and audiophiles donāt understand what they are enjoying is a degradation of their playback chain. Thatās a stretch for me though. Bottom line it would be measurable as the outputs of a DAC are voltage output devices. Regarding disconnection of the cable, putting aside the possible significance of airborne RFI doing so would of course work in the direction of reducing noise that may be coupled from the input circuitAgain this is measurable. Also why I like WiFi. Itās low latency, high throughput, no measurement (either instrumented or human) shows harmonic componentās of RFI frequencies showing up. I think you just said that removing the plug from the back of the client would work in the direction of reducing noise... So with that said I would encourage a blinded evaluation session where the Ethernet cable is removed during playback of a track and the listener successfully is able to indicate that removal or insertion. Letās even paint a scenario where thatās actually the case. That noise component is most likely going to be buried in the noise floor (or a component of) the DAC, in the -130dB range on a competently designed piece of gear. You canāt hear anything that low even if itās there. And if itās not. Itās not. Putting it all very basically, responses by those claiming ethernet cables wonāt make a difference nearly always focus just on the intended/nominal signal path. The basic point to my earlier posts is that in real world circuitry parasitic signal paths also exist (via grounds, power supplies, parasitic capacitances, etc.), which may allow RF noise to bypass the intended signal path to some extent, and therefore may account for some or many of the reported differences. Your response sounds like a guess. I have another theory for all the differences and itās sighted bias or really poorly designed, often expensive, equipment. Iāve been recommending either WiFi (ubiquiti) of wired (Intel Server PCIe) NICās (left and right they are available NIB or as new but pulled) for for ~$25. They seem impervious to what cabling Iāve thrown at it. |
I purchase a 25ft Supra Cat 8 about 6 mos ago. I installed it for a bit and did not really notice an uptick in Sq. So I took it out as I did not feel like getting under the house to do a permanent install. I recently up dated my cable loom to the Audience Au 24Sx series. I re installed the Supra after a couple mos of breaking in the Audience and a very nice bump in Sq. Deeper soundstage, more defined percussion, better high end. Pretty easy to hear the improvement.Ā So the answer is if you have a very resolving system an upgraded Ethernet cable will definitely help. Ā Just proved it in my system.Ā |
Where in the playback system are you referring to this jitter?I am referring to timing jitter at the point of D/A conversion. And I am referring to the possibility that cable differences may affect the characteristics of RF noise that may bypass (i.e., find its way **around**) the ethernet interface, buffers, etc. and **to** the circuitry that performs D/A conversion. Regarding disconnection of the cable, putting aside the possible significance of airborne RFI doing so would of course work in the direction of reducing noise that may be coupled from the input circuit to the point of D/A conversion. The 1,000,000,000 ns of jitter you referred to has no relevance to that. Putting it all very basically, responses by those claiming ethernet cables wonāt make a difference nearly always focus just on the intended/nominal signal path. The basic point to my earlier posts is that in real world circuitry parasitic/unintended signal paths also exist (via grounds, power supplies, parasitic capacitances, the air, etc.), which may allow RF noise to bypass the intended signal path to some extent, and therefore may account for some or many of the reported differences. Regards, -- Al |
Thatās interesting. Can you please tell us more about your comparison? Was it based solely on measurements? If you conducted listening tests, can you please tell us how they were conducted? Which specific cables did you evaluate? Nordost Heimdall 2 one meter $699.Ā BerkTek Hyper 5e, 98 meters, $90.Ā Cary Audio DMS-500 RME UFX A/D duties fed to my laptop ARTA for measurements. Nothing in spectral components, nothing in the 11.25Khz jitter, nothing in the linearity testing, nothing in the noise floor. I also did a cascade plot with my measurement mic. Nothing changed other than room ambient noises from one run to the next. This would even be slightly different using the same cable on multiple runs.Ā I also captured the tracks and posted them elsewhere for people to download and evaluate. During playback I swapped out the cabling and simply asked for people to tell me when the cabling was swapped. Only a handful tried and all failed.Ā |
Such as to D/A converter circuits, where timing jitter amounting to far less than one nanosecond is recognized as being audibly significant. (See the section entitled "Jitter Correlation to Audibility" near the end of this paper). This is where we have a problem. Where in the playback system are you referring to this jitter?Ā The entire point that, and I will keep with Tidal as example, is that once local buffer is filled up, and buffers are indeed static storage, that any timing variance ceases to exist. It's why I can watch Netflix 4K streamed with no issues.Ā The fact of the matter, and it is indeed FACT, is if I pull the network cable for 1 second I've introducedĀ 1000000000ns of jitter but some how the playback system has managed to deal with this and deal with it to the point that if you are blinded you couldn't tell me if your life depended on it.Ā While this timing difference may be in the DA converter circuits, that's not the same as Ethernet which is burst in nature and asynch.Ā In addition to the effects of shielding on radiated emissions, shielding would presumably also affect the bandwidth, capacitance, and other characteristics of the cable, in turn affecting signal risetimes and falltimes (the amount of time it takes for the signals in the cable to transition between their two voltage states), in turn affecting the spectral composition of RF noise that may find its way past the ethernet interface in the receiving device. If your playback equipment is susceptible to standards compliant Ethernet cabling affecting playback I would say your equipment is defective.Ā Again using Tidal: When I was at WGUtz place the 100', $13 cable allowed Tidal to cache the entire track just as quickly as the 15' boutique cable.Ā Modern PHY's put the interface into a low or no power state when not transmitting. An 11 minute song was cached, in it's entirety, in about 15 seconds.Ā Obviously noise that may find its way to circuitry of the receiving device that is downstream of its ethernet interface, as a consequence of the signal it is receiving, will be eliminated. On the other hand, airborne RFI may increase since the cable would no longer be connected to a termination that would absorb the signal energy. Which of those effects may have audible consequences, if in fact either of them does in some applications, as I indicated in my previous posts figures to be highly component and system dependent and to have little if any predictability.Then everyone is screwed. I don't believe that to be the case. I can build a world class client / server setup for $700 to feed a DAC. I donāt doubt your experience. However, I also donāt doubt experiences that have been reported by members such as DGarretson, Bryoncunningham, Grannyring, and others here who are similarly thorough when assessing a change. You should doubt me and everyone else. The difference being I actually showed up at a members house and we went through this where the perceived changes disappeared once sighted bias was controlled for.Ā I have no problem doing this elsewhere.Ā |
jinjuku Iāve personally had Ethernet cabling from $27 a foot to $233 a foot and compared directly to 315 foot of BerkTek CAT5e. No difference.Thatās interesting. Can you please tell us more about your comparison? Was it based solely on measurements? If you conducted listening tests, can you please tell us how they were conducted? Which specific cables did you evaluate? |
Homes donāt have these challenges. So the shielded designs donāt help, but they could hurt if the shield ties end points to chassis and creates a ground loop. Floated shield would be fine however and the costs are minimal if it makes the audiophile feel better.I agree that shielding is not needed in a home environment to assure that communications on the ethernet link are robust and reliable. However I wouldnāt rule out the possibility that it could make a difference with respect to RF noise that may be coupled **from** the cable **or** from the input circuit of the receiving device to circuit points that are downstream of the ethernet interface in the receiving device. Such as to D/A converter circuits, where timing jitter amounting to far less than one nanosecond is recognized as being audibly significant. (See the section entitled "Jitter Correlation to Audibility" near the end of this paper). In addition to the effects of shielding on radiated emissions, shielding would presumably also affect the bandwidth, capacitance, and other characteristics of the cable, in turn affecting signal risetimes and falltimes (the amount of time it takes for the signals in the cable to transition between their two voltage states), in turn affecting the spectral composition of RF noise that may find its way past the ethernet interface in the receiving device. Also, small differences in waveform distortion that may occur on the rising and falling edges of the signals, as a result of less than perfect impedance matches, will affect the spectral composition of that noise while not affecting communication of the data. When someone teeās up a track in Tidal on their 100Mb/s cable modem and they pull the Ethernet cable and the song still plays what is actually happening from a cable perspective at that point? Obviously noise that may find its way to circuitry of the receiving device that is downstream of its ethernet interface, as a consequence of the signal it is receiving, will be eliminated. On the other hand, airborne RFI may increase since the cable would no longer be connected to a termination that would absorb the signal energy. Which of those effects may have audible consequences, if in fact either of them does in some applications, as I indicated in my previous posts figures to be highly component and system dependent and to have little if any predictability. Iāve personally had Ethernet cabling from $27 a foot to $233 a foot and compared directly to 315 foot of BerkTek CAT5e. No difference. I donāt doubt your experience. However, I also donāt doubt experiences that have been reported by members such as DGarretson, Bryoncunningham, Grannyring, and others here who are similarly thorough when assessing a change. Regards, -- Al |
@ burghĀ I wired up heavy machining plants in Wixom, Mi, Cleveland, Oh, Youngstown, Oh, Mentor, Oh etc... Didn't matter if it was Ethernet or 485 Serial it was always shielded because all the 3 phase power and large inductive motors.Ā Homes don't have these challenges. So the shielded designs don't help, but they could hurt if the shield ties end points to chassis and creates a ground loop. Floated shield would be fine however and the costs are minimal if it makes the audiophile feel better. No one is saying don't use quality cabling. But the fact remains that the highest performance Ethernet cable out there is Belden's 10GX and it's about $2/foot terminated.Ā You can get their normal bonded pair CAT6 for ~$1.40 a foot.Ā I've personally had Ethernet cabling from $27 a foot to $233 a foot and compared directly to 315 foot of BerkTekĀ CAT5e. No difference.Ā |
I have no audio on EthernetĀ but I can't imagine the quality of the cable NOT having some influence. I work for a company thatĀ we specialize in Industrial Automation products. Everything talks to one another over Ethernet or in my world Profinet. PLC;s talking to Variable Frequency Drives, Industrial PC'sĀ etc. We DO NOT use your Radio Shack / Walmart cables. We use a industrialized cable that is shielded to protect the signals from noise. We actually terminate the cables with shielded Metal connectors made specifically for this cable. I am not sure you would need that, but if you think you would let me know. |
Pop Quiz A Google search for āsignal speed copper vs fiber optic cableā turns up this explanation at the top of the page. Find the mistakes. āFiber optic transmission is faster: Fiber optic versus copper wire transmission can be boiled down to the speed of photons versus the speed of electrons. ... And while fiber optic cables donāt travel at the speed of light, they come very close ā only about 31 percent slower.ā Extra credit. Does an electromagnetic wave travel faster through water or glass? |
Transmission speed is going to be dependent on the conducting material, and correct me if I a wrong, Cat levels are bandwidth capabilities enabled by the reliability of the signal, therefore the shielding around each core. The transmitter/receivers at each end are going to have a significant effect on this. Optic fibre is good for data and low level audio. I believe @geoffkaitĀ stated that jitter was a debilitating effect on music over OF. I would imagine that this to will be overcome in the future. |
I love it when somebody wants to convince the world that they are right by stating they talk to an engineer and he said blah blah blah! I donāt give a rats @$$ What an engineer says, if you have to rely on somebody elseās opinion then you donāt know what you are talking about. Also, There are differences in network cables running into your house. Iām guessing you have copper of some sort, which is noisy. I have fibre and fibre is always going to be less noisy than copper. Ask your guru buddy about that. Everybody on this thread talks about the speed differences between cat5 to cat8 cables, in reality, itās more than just speed differences, much more between the different cables. Cat5 speed rating is far more than what you need to transfer digital music. Cat5 has much better throughput than the throughput from a CD player. If you check out the cable sheathing and shielding, it is much better on the cat7 and above cables. |
It seems to me that what has been largely overlooked in this discussion (with the exception of the brief post by Markalarsen) is the fact that 100% of the energy of an electrical signal, especially one that as in the case of Ethernet contains spectral components at very high RF frequencies, does not necessarily go only where it is supposed to go. Experienced designers of high speed digital circuits (of which I happen to be one) will recognize that. And I encourage and invite every last one of you to, in your own setup, to evaluate some spec meeting, but very inexpensive, CAT5e/6 to your own esoteric CAT5e/6 cabling. Iāll provide a client, server, layer 3 managed switch with a LAG setup for dynamic LACP. Of course you will not be allowed to know which cable is being used. |
Just as a matter of fact, ethernet doesn't always use TCP/IP because there isn't really a "TCP/IP" protocol. Those are two different protocols for two different layers of the software interface. In all likelihood, it's using TCP/FTP. You have a gross misunderstanding. There is indeed a TCP/IP protocol. It's transmission control protocol over internet protocol. UDP/IP is also a protocol. Ethernet isn't any one protocol. It's made up of many moving parts and the abstraction it provides up/down stream layers is why it's so robust, reliable, and elegant. There is no such thing as TCP/FTP because FTP doesn't live at layer 3. It's layer 7 (application). |
@jinjuku what do you mean by 60% reliability? @acepilot71: William chose the testing format. I randomly generated a sequence of cable swap out. William went with either listening to an entire track or part of a track. He only obtained 60% accuracy of stating what cable was in use. Which means he was also in error 40% of the the time. |
John Archibald Wheeler and Kip Thorne wrote the definitive book on the subject of gravity many years ago, Gravitation, 1973, 1336 pages. Everybody and his brother now knows that gravity is actually the warping or distorting of spacetime as a consequence of mass. Thatās the reason the LIGO Project detected gravity waves a couple years ago. It detected gravity waves created by a merger of two monster size black holes. The LIGO sensors detect ripples in spacetime. The head of the LIGO Project for most of its life was Kip Thorne, former student of Wheeler and co-author of Gravitation. Addendum for the advanced student: Considering the notion that positrons were electrons that were traveling backwards in time, Wheeler came up in 1940 with his one-electron universe postulate: that there was in fact only one electron, bouncing back and forth in time. His graduate student while was a professor at Princeton, Richard Feynman, found this hard to believe, but the idea that positrons were electrons traveling backwards in time intrigued him and Feynman incorporated the notion of the reversibility of time into his Feynman diagrams.[24] With Neils Bohr Wheeler helped explain nuclear fission. |
