Has nothing to do with HV potentially coming down. None at all :whistle:
As for trusting companies... I agree with you except we would be essentially back to smacking two rocks together to make fire without them. I'll go with cautious trust.
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Apple's Interest in WiTricity Wireless Charging
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As for trusting companies... I agree with you except we would be essentially back to smacking two rocks together to make fire without them. I'll go with cautious trust.
You can get magnets without electricity. "loadstone" However, all electricty in forms magnetic fields, whether static (DC elctromagnets) or alternating magnetic fields.Cheers mate,
Your distinction to the differences are only academic. Fundamentally they are linked and are the same; only being that one describes the interactions between matter, and the other describing it how it travels through space in the form of energy.
But you are probably a bit behind the times; the two theories were 'unified' in the 19th century by Faraday, Maxwell, et al.
Just remember one thing about it. Neither can exist without the other. A magnetic field is created by an electric current. Or maybe the other way around? Hmmm... I think I forget...
Cheers mate,
Your distinction to the differences are only academic. Fundamentally they are linked and are the same; only being that one describes the interactions between matter, and the other describing it how it travels through space in the form of energy.
But you are probably a bit behind the times; the two theories were 'unified' in the 19th century by Faraday, Maxwell, et al.
Just remember one thing about it. Neither can exist without the other. A magnetic field is created by an electric current. Or maybe the other way around? Hmmm... I think I forget...
They are necessary to each other's existence, but only in EM waves. However, EM radiation and B-fields [magnetic fields] aren't the same. They are linked, though. As for what induces what, they can [and do!] both induce each other - current induces B-fields and [changing] B-fields induce an emf that "pushes" a current.
*Lodestone. And they do produce magnetic fields, but no magnetic waves. In electromagnetic radiation [comprised of EM waves], HowieR32 is correct that the wave can only exist with both an electric wave and magnetic wave component. As they alternate, they induce an opposing change in the other. You could imagine it as them "driving" each other.
Well now I am off to google to find out why sun exposure is correlated with skin cancer. Ahh, the Ultraviolet section he mentioned, brain must be asleep... Microwave is 10 to the -2 and Ultraviolet is 10 to the -8 in wavelength. I am assuming the power sources we are talking about are the Electrodynamic induction method which uses waves about 6 times the distance they are optimized to resonate (if I understand correctly) so very long wavelengths, no where near the energy needed to break chemical bonds. Man the internet is cool.
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^Yes, the wavelength they use is in the order of metres! Even longer wavelengths than FM radio.
Of course I won't trust WiTricity's marketing. If you read the post you quoted I specifically said to try and go to primary sources if possible. I looked up pier reviewed scientific papers online. I looked up the magnetic field produced (tiny as this method doesn't rely on really strong magnetic field to work) as well as the frequency it operates at (~10MHz). I can't state it's 100% safe, but I can say that people getting worked up about magnetic fields are missing the point.
Of course I won't trust WiTricity's marketing. If you read the post you quoted I specifically said to try and go to primary sources if possible. I looked up pier reviewed scientific papers online. I looked up the magnetic field produced (tiny as this method doesn't rely on really strong magnetic field to work) as well as the frequency it operates at (~10MHz). I can't state it's 100% safe, but I can say that people getting worked up about magnetic fields are missing the point.
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Sorry Mate, but I think you have your numbers mixed up.
What is stated in the MIT paper is that the magnetic field needed to charge the device is about 0.1 uT. Considering that the strength of a magnetic effect is vastly reduced (don't remember if it's a negative square or even cube function) this would amount to a much stronger field needed to be generated to get a 0.1 uT Field at a distance of a couple of meters.
This is also the reason why efficiency drops dramticaly by distance.
But without getting picky on numbers, the concept of flooding my home with a magnetic field just makes me uneasy. I may be a bit too cautious about this but even though many scientists state that no negative effect of power landlines above playgrounds / kindergartens / schools has been proven, the high numbers of leukemia at those institutions indicate that it is at least likely that there is a relation between the two.
To sum this up (and this holds also true to the various scientific reports posted in this thread) we just don't know (yet) how strong a magnetic field has to be and how long one has to be exposed to suffer negative effects. So I will continue to not have my dect phone nor my cellphone being next to my bed and deactivate my wlan over night...
Actually it hasn't been proven at all. At best there is a mild correlation but scientists have never been able to adequately control for other carcinogens which represent confounding factors in observational studies.
This article is about the strongest endorsement one can find for your point of view, but even it doesn't go so fa as to say that a cause actually been found; it says that further study is needed before any conclusions can be made.
You are free to deactivate your cell phone's radio at night if you are paranoid about any health risks, but don't confuse that paranoia with evidence.
It has not been proven. I think you're referring to the 2004 British Medical Journal article that found an inexplicable increase in leukemia in children living near power lines in England and Wales. The researchers wrote: "There is no accepted biological mechanism to explain the epidemiological results; indeed, the relation may be due to chance or confounding."
In 2003 a similar study found no causal connection between living near power lines and developing breast cancer. You can't rely on but one study (or even a few studies) to prove a link, and all conclusions must be in agreement with the preponderance of evidence and scientific understanding. Our understanding is that there is no reason for EMF to cause cancer, and therefore the burden of proof is substantially on those claiming there is a correlation. Seeing that the evidence is so weak, chance is the more likely explanation for the 2004 results, not actual correlation. The burden of proof has not been met, and research has been ongoing for many, many years. If there was a correlation it would be very easy to find.
http://www.skepdic.com/emf.html
Well it's nice to see someone actually look at the paper! I've been trying to steer clear of decay in too much detail because it's just adding more complexity, but of course there is decay at distance. Yes, in proper terms the magnetic field would need to be 0.1uT at 1 or 2 metres.
I am trying to give examples at reasonable distances. A typical TV will expose you to 0.1uT at a metre or so but a few centimetres away it will be a couple of orders of magnitude higher. An electric razor can be in the mT range a couple of centimetres away, and many people use that every morning! The point is the exposure this WiTricity would yield is low the majority of the time. Yes it will be higher close up (still very low though) but if 0.1uT is all it takes to charge something like a phone then that is all we need to sit in when we are at our desks or on our sofas. Yes you may get a higher "dose" as you walk past the emitter but that is a short period of time and no different to walking past someone vacuuming, or even just sitting by a desk lamp. As an undergrad I worked with NMR machines millions of times stronger than the numbers I'm talking about here!
However, I agree we shouldn't get too bogged down in numbers. The kind of levels we are talking about are very low, and magnetic fields don't appear to interfere with organic life. Certainly there's no real evidence to suggest power lines are dangerous!
Wireless charging - I don't want it
We don't want it for at least two reasons:
1. Health hazards: Electromagnetic field will introduce current flows in metals like amalgam tooth fillings, thus releasing more poisonous mercury.
2. Wireless power transfer will always have greater losses than real connections. Why have 10 nuclear reactors supplying wireless products instead of 8 supplying connected products? Maybe the last one or two are the ones breaking down ... Or why have unnecessary carbon emissions when we anyway should decrease them?
We don't want it for at least two reasons:
1. Health hazards: Electromagnetic field will introduce current flows in metals like amalgam tooth fillings, thus releasing more poisonous mercury.
2. Wireless power transfer will always have greater losses than real connections. Why have 10 nuclear reactors supplying wireless products instead of 8 supplying connected products? Maybe the last one or two are the ones breaking down ... Or why have unnecessary carbon emissions when we anyway should decrease them?
What is a Typical TV these days? A CRT may expose you to those levels at those distances, but a modern LCD / Plasma should not, unless it has a bad or horribly inefficient inverter.
Also, there is a huge difference between sitting in front of a TV for a period of time, or using a razor, when compared to sitting in a room that is saturated with EMF at all times. Since the point of this technology is overall freedom of wireless power, it doesn't make sense to limit the wireless power to small hot-spots within a room.
It is quite clear in this image, that WinTricity's goal is intended to (perhaps eventually) energize entire rooms, not small sections. Wile this could be a PR sided poster, I would expect their customers would complain about limitations, and eventually WinTricity would expand to full room, or full house systems down the road.
Also, I don't believe that most people worried about EMF are concerned with momentary or brief flashes of high EMF, but more with the cumulative exposure. While not paranoid about it, I do share this concern.
FWIW I own, and have access to multiple Tesla / Gauss meters. And no, not the K2 style from the ghost hunting shows
. They are used to check for high EMF fields within the Datacenter I work in. They are helpful for various things for the facility, including checking for possible interference with both Ethernet and Wireless networks.
They are probably looking towards that, but for now I think the real life examples are more like hotspots (and very likely the first consumer products). It would be great to power everything one day.
I'm not sure exposure to energy sources works that way. Chemicals can build up in the body over time, becoming toxic at high enough concentrations. However, a photon/wave/energy etc doesn't linger. If the energy/strength isn't enough to cause any effect then continued exposure won't make any difference. There needs to be some sort of impact for a cumulative/continual effect to occur (like how a microwave works). If the EMF is too weak to do anything then sitting in it constantly is fine, and the scientific consensus is that at the kinds numbers we are seeing with WiTricity there is no need to worry.
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Actually, the entire Scientific community is not split. The entire scientific community whole heatedly believes that the earth is warming. Not just people that study climate believe this either, many scientific discipline are seeing their areas of study being effected by a changing climate. Species are dying, ice is melting, and deserts are growing while other areas flood.
The only thing scientists are remotely split on is to what degree humans are causing it, yet they all agree that humans have had a large impact.
So I submit for your review the following articles:
From The Gaurdian (your source of choice) on how "Climategate" is based on out of context quotes and weaving together emails that were written 10 years apart.
The Gaurdian again:
"Climategate scientists cleared of manipulating data on global warming. scientists did not fudge data, but they should have been more open about their work"
From Factcheck.org on "Climategate":
"Hacked e-mails show climate scientists in a bad light but don't change scientific consensus on global warming."
And finally, The New York Times
"First of all, we didnt fail to act because of legitimate doubts about the science. Every piece of valid evidence long-term temperature averages that smooth out year-to-year fluctuations, Arctic sea ice volume, melting of glaciers, the ratio of record highs to record lows points to a continuing, and quite possibly accelerating, rise in global temperatures.
Nor is this evidence tainted by scientific misbehavior. Youve probably heard about the accusations leveled against climate researchers allegations of fabricated data, the supposedly damning e-mail messages of Climategate, and so on. What you may not have heard, because it has received much less publicity, is that every one of these supposed scandals was eventually unmasked as a fraud concocted by opponents of climate action, then bought into by many in the news media."
Nor is this evidence tainted by scientific misbehavior. Youve probably heard about the accusations leveled against climate researchers allegations of fabricated data, the supposedly damning e-mail messages of Climategate, and so on. What you may not have heard, because it has received much less publicity, is that every one of these supposed scandals was eventually unmasked as a fraud concocted by opponents of climate action, then bought into by many in the news media."
I'm aware that this is wholly off topic. But I hope it demonstrates that the pundits, one liners, and headlines that get paraded around the world at the onset of "Scandal" aren't the entire truth.
The idea that the Scientific community is in disagreement over this is another lie. I was listening to NPR the other day as they talked about climate change. The scientist on the show said the saddest thing about the entire Climate Change ordeal is that Scientists are not being loud enough. He said too many of them are happy enough to write down the truth in a journal and have it published someplace. In reality the Scientific community is being attacked and bombarded by politics and economic interests and they (as a community) don't know how to respond.
There was a time when scientists were trusted. And now through no fault of their own, the american public has no faith in them or their field. If there will be any downfall to this country, that will be it.
To veer slightly back on topic.
The following is aimed at no one in this thread specifically, especially the person I quoted above.
The Scientific community for me is where it's at. I trust them to tell me what type and intensity of EMF will cause my body harm, do you know why? Because they are the ones with the knowledge to actually figure it out. Anything else is just dice rolling and/or paranoia. And while it's fine if an individual chooses paranoia for themselves, do not attempt to slander the scientific community in an effort to get me to live in your world. Since they are human, they do make mistakes. Sometimes they aren't even involved in the decision to say it's safe (like asbestos) but you can be damned sure they were the ones to figure out WHY it's not safe later on.
Okay, rant over
Now I'm back to work...
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Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8F190 Safari/6533.18.5)
Hasn't Tesla already done this? Perhaps Apple bought his patents
Amen, too much info out in the world now, at least now no one is gonna get thrown off a boat and their lifes work stolen from their office
First off, thank you for the info! I'm pretty ignorant when it comes to biology; my field is physics.
I wasn't saying that the magnetic field would induce a current - it wouldn't be able to do that because 1) neurons aren't made of conducting materials [at least, I don't think they are] and 2) they aren't loops, they're just little line-like objects. For the B-field to induce a current, it has to travel through a closed conducting loop [like a circle of wire]. So an induced current isn't really possible. Although, it'd be pretty weird if it was! Aren't "thoughts" essentially electrical impulses through neurons? Would an induced current be equivalent to "giving" someone a thought? Weird stuff.
Anyways, what I was saying was that since a charged particle [like the ions you mentioned] moving through a B-field has its trajectory warped, it might be possible for the impulses through neurons to become disrupted/changed/lost/etc. Which would certainly affect the brain. I do know however, that between neurons, where charges would be "free", only neurotransmitters flow [no electric current or charged particles]. So if all charged particles were insulated inside the neuron by the myelin sheath [which is what I think the function of the sheath is], then no effect would be observed. Assuming, of course [big assumption], that I correctly understand neuron biology.
And what would be the effect on the brain if there were "alignment of polar molecules to the field"? What are the polar molecules in the brain, and how would their disruption[?] affect the brain's function?
All in all, however, given the very weak strength of the B-fields involved, I would put forth a cautious guess that this technology is completely safe. The bigger issue seems to be its efficiency.
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My thoughts exactly.
My thoughts exactly.
Depends on how you define "Charging"
Are you sure they don't mean a new way of "charging" as in a NFC-based contactless payment solution?
In other words, integrating your credit cards into the phone so you can pay by simply holding your phone up to a sensor and activating a credit card signal with a pin of some sort when you want to pay for something...
Are you sure they don't mean a new way of "charging" as in a NFC-based contactless payment solution?
In other words, integrating your credit cards into the phone so you can pay by simply holding your phone up to a sensor and activating a credit card signal with a pin of some sort when you want to pay for something...
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Yes we are sure they don't mean that. Read the article, or google WiTricity.
Debatable
Seeing as though the only quote that is fueling this speculation is "a new way if charging" I'd say that your assertion is debatable. Just because macrumors referenced witricity as an existing technology doesn't mean that's the truth. It's far less likely to show up in iPhone 5 than NFC payment. It may even be that both technologies end up in the phone, I was simply noting that the "tip" could be construed differently. You charge your credit card and you charge your phone.
Seeing as though the only quote that is fueling this speculation is "a new way if charging" I'd say that your assertion is debatable. Just because macrumors referenced witricity as an existing technology doesn't mean that's the truth. It's far less likely to show up in iPhone 5 than NFC payment. It may even be that both technologies end up in the phone, I was simply noting that the "tip" could be construed differently. You charge your credit card and you charge your phone.