Tech Giants Tilting at Windmills

Much ado was made this week of Facebook launching a solar powered drone to bring the internet to all. It may sound like a noble goal, but beware of the physics.

Facebook’s push is another example of Silicon Valley stepping outside its realm of expertise to try to do something that probably won’t work. Google is trying to do the same thing as Facebook, but with balloons instead of drones. The idea is this: build lots of little tiny aircraft and send them everywhere in order to relay the signal to people who don’t have it. Keep in mind that Facebook (and Google) are both held together by people whose predominant expertise is writing computer programs…

Now, the reason I call this set of ideas tilting at windmills is simple: they are trying things somewhat randomly hoping that the technology will catch up just in time for implementation without thinking about what making it work will mean to the world around them. Silicon Valley is trying desperately to roll out the 5G wireless standard in the next five years. Here is a list of the fundamental criterion for 5G taken from wikipedia:

  • Data rates of tens of megabits per second for tens of thousands of users
  • 1 gigabit per second simultaneously to many workers on the same office floor
  • Several hundreds of thousands of simultaneous connections for massive wireless sensor network
  • Spectral efficiency significantly enhanced compared to 4G
  • Coverage improved
  • Signalling efficiency enhanced
  • Latency reduced significantly compared to LTE.[2]

Sounds kinda wonderful does it? Got to admit, downloading a whole movie in seconds to minutes instead of hours would be wicked nice!

Now, the trick here is how. How do you do this?

The way that the physics of light interface with electronics is very strongly tied to clockspeed in a computer. This is how fast your processor makes calculations (after a fashion). As transistors have gotten smaller, the amount of energy needed to switch them has gone down and the switching rates have gone way up in conjunction with the number of transistors present. Modern 4G technology interfaces with light at frequencies of 2.5 GHz and 5 GHz (that is roughly 5 billion switchings a second) using 40 MHz to 60 MHz frequency modulation bands at around those frequencies in order to transfer the data. With compression routines based on frequency convolution, this microwave light can transfer between 5 and 12 million computer bits per second with as much as 100 million bits per second. 5G will supposedly do 100 to 1000 times that: 12 billion bits per second. In order to handle this enhancement of speed, 5G will be broadcast at microwave frequencies of something like 40 to 60 GHz.

One thing all these wonderful stats aren’t telling you about is a physical phenomenon called Penetration Depth. As light travels through any medium, the intensity of the wave is gradually absorbed by that medium and reduced until it goes away. As you drive away from a radio station, eventually, the 1/r^2 reduction of power with distance and the atmospheric attenuation with penetration depth conspire to make your radio reception go away. For the broadcast frequencies used by radio stations, this is a couple hundred miles distance. Such stations have good range in large part because they don’t need to transfer horrifyingly large quantities of data: everybody gets the same broadcast and that broadcast doesn’t need a very high frequency to transfer the information required: AM radio is only in the hundreds of kHz (hundreds of thousands of switchings per second, roughly 10,000 fold slower than 4G).

Now, 4G is exactly the same thing as old timey radio, except that everybody with a smartphone gets their own unique broadcast and then broadcasts signals back to the tower in return. Everybody is their own TV station. That is, of course, why 10,000 fold faster was needed.

Now, penetration depth for a 4G station is different than for a 200 kHz radio station. As it turns out, penetration depth is inversely proportional to frequency. The penetration depth for a 4G signal is 1/10,000th of the depth of an AM radio signal in atmosphere. Receivers have gotten more sensitive since the AM radio revolution, but the physics has conspired to limit reception distances for the 4G signal to just a couple miles. Literally, after you get out of direct line of sight with a 4G cell tower, the signal is gone. This is why there are now ugly cellphone tower trees everywhere you look!

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The signal doesn’t go very far, so the antennas need to be everywhere.

5G now is going to be set at 10-fold higher frequency than 4G. That means 5G has 1/10th the penetration depth of 4G. This changes miles into hundreds of yards.

In order to support 5G, there will need to be many many more antennas (think factor of ten). You can’t get around it physically. You will need one in your home and probably one directly in your car.

Now then, what does this mean for our merchants of signal from above? Google and Facebook have no choice but to be unable to deliver 5G wifi directly from their balloons or drones. Do you really think anybody can support the infrastructure for floating a balloon or drone every couple hundred yards, no higher than a couple hundred yards, everywhere, all the time? For one thing, Helium is a precious commodity that is ultimately more scarce than fossil fuels. 5G will certainly happen, but is this the way we really want for it to be implemented?

I think I personally would be out skeet shooting. People will eventually call enough. Do we really need Silicon Valley doodads flying everywhere, 24/7? Get ready for it… people will try it.

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Flat Earth Swan Dive

There is an article out today that Stanley Kubrick’s daughter spoke out vehemently against the idea that her father, the legend himself, helped NASA fake the moon landings. She called it ‘grotesque.’ I thought it was an elegant response to an insane and stupid idea. You hear that popular culture? The moon landing was not faked. Point a laser at the retroreflector if you don’t believe me. (IIRC, there are also now satellite images from LRO of the original lunar landing sites, but then someone favoring the moon hoax would claim those are doctored)

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While I was reading the comments to this article, I stumbled over a flat earther making his/her case. This person laid it out in a bulleted list saying “You have to accept or believe all of these inconsistencies in order to accept that the Earth is round,” and I could not help but write a comment replying to him. Since one of the purposes of this blog is to be a repository for the times I feel compelled to speak up in comment sections, here is an edited copy-paste of my original comment, which responded directly to each bullet point made by the flat earther.

>1. You are traveling 19 miles/second and you feel none of it.

And your point is? You can feel accelerations, not velocities. You can be in a train traveling 300 miles/hour with the shades drawn and not know it.

>2. The Earth is spinning at 1000 miles per hour and you feel none of it.

So? You feel accelerations, not velocities. Further, the only acceleration you feel in the rotation of the Earth is in a similar direction to gravity. Are you good enough to be able to tell the difference between gravity and centrifugal force?

>3. If you could dig a hole right now through the the earth you would eventually hit sky.

So? We have satellites that take pictures of this all the time. That the Earth is round is pretty well documented. Do you think these pictures are all generated only by NASA? I’m sure SpaceX has a couple.

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>4. The Earths diameter is 7917 miles which means there is someone standing upside down in relation to you less that 8 thousand miles away right now, yet you are both unaware of it.

So? Would you be aware of someone 8,000 miles away if they were standing next to you instead of below you? I would wager not.

>5. Water can be shown to always find it’s level except on a planetary scale. Which means there is a wall of water 13000 statue of liberty’s high between California and Hawaii and only magical gravity keeps it from flooding the United States mainland.

Now you’re just being stupid. Gravity pulls downward locally, which is a different direction at Hawaii from the direction at Los Angeles. This is the nature of the solution of gravity from a sphere. Toward the center of the sphere!

>6. The nearest star is 25 trillion miles away which is why we never see parallax. Or have to explain parallax.

Parallax has been used to fairly accurately calculate the distance to the moon and the sun. It’s also been used to estimate distances to near stars. Why in the world have you included this point? In fact, the way parallax is used to calculate stellar distances really kind of harpoons your whole argument.

>7. The Chicago Skyline, from the opposite side of lake Michigan 60 miles away, is a mirage as the tallest building there should not be visible behind the earths curve. Yet it has been seen and photographed time and again.

Optical effect. Same thing as the green flash seen at the surface of the ocean when the sun goes down. Light is known to not always travel in straight lines and the conditions when it doesn’t are pretty completely understood. There’s even a name for the kind of mirage that lets you see Chicago from across the great lake: the Superior Mirage. Or, do you actually believe you’re seeing the sky below the road when you see a mirage on a hot day?

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>8. The Coriolis effect has no effect on airplanes, yet is said to have an effect on munitions.

Dude, learn something about the Coriolis force. Munitions are unpowered while airplanes can continuously exert an acceleration. Of course Coriolis force must be corrected for to fly an airplane, but the airplane can actively maneuver throughout its flight to compensate.

>9. Firing a gun or cannon east or west will not be helped or hindered by the apparent rotation of 1000 miles/hour which means the Coriolis effect can be selective.

Flat out False: NASA launches rockets toward the east in order to take advantage of the surface velocity of the Earth to help reach orbit with less fuel. Further, Kennedy Space Center and Cape Canaveral were built in Florida in order to place them at the location in the continental United States that gives the greatest rotational kick during the rocket launch (closest to the Equator). They don’t need as big of rockets when they use Coriolis force in this way. You really should bother to learn some physics. It would surprise you to know that the Earth bulges away from spherical by something like 20 miles at the equator because of centrifugal force (How do they know this? GPS, dude.)

Moreover, if you’re using the GPS on your smartphone to travel anywhere, and you are espousing this sort of nonsense, you’re the biggest hypocrite alive.

>10. Gravity is strong enough to keep you and everything you see firmly stuck to the earth, yet birds and insects seem completely unaware as to the 1000 miles/hour rotation and have no trouble over coming gravity.

Bernoulli force, dude. You’re not impressing me. Do you think the wind should somehow be whipping past at 1000 miles/hour, as if the atmosphere was unhinged from the surface of the planet? Again, within the local frame of reference, the only acceleration you feel is along the direction of gravity and you can’t discriminate centrifugal force from gravity without a gravitometer. Further, the atmosphere is fairly tightly bound to the surface of the planet and mostly travels with the Earth as it rotates: in order to see effects of the Coriolis ‘force,’ you need to have a definite velocity and relatively little friction with the atmosphere. An object the size of a bird gets carried along by the atmosphere, which is interacting strongly with the surface on the scale of many miles.

>11. The wobble of the planet tilts sections of the equator to 45 degrees at distances that normally would be occupied by arctic tundra. Yet those same sections never form glaciers.

The tilt of the Earth is not the only factor determining the climate of regions on the surface. We have huge oceans that act as giant circulating heat sinks that move heat to places that might not otherwise receive light. Feel the wind? That moves heat too.

Moreover, the tilt of the earth is only ever 23 degrees from the plane of the ecliptic. This 45 degrees garbage is the full swing from extreme north to extreme south passage of the sun at the apex of the local sky during the solstices. The arctic circle is 66 degrees from the equator and the angular distance between arctic and antarctic circles is about 130 degrees. You have wildly expanded an angle somewhere.

>12. The moon takes the same path through the night sky each night in a 29.5 day cycle yet the shadows cast by moon phases would seem to suggest that the moon is not taking the same path through the night sky each night.

Rotation of the Earth, dude. Did you know that the moon actually travels in a west to east direction around the Earth? I’ll bet you didn’t. As the moon orbits, roughly 1/29th of its orbit around the Earth per day, the time when it rises during the day is displaced by 1/29th of the Earth’s day-long rotation cycle. Why do you think the moon never quite rises at the same time? It rises about 50 minutes later than it did the day before every single day.

>13. The summer solstice and winter equinox should completely flip our high noon and midnight with each 6 month rotation, but does not some how.

This is because you’re misunderstanding something about the travel of the earth around the sun: there is exactly no set period relation between the earth’s rotation and its revolution around the sun. The period of the year is only approximately 365 days… it’s actually 11 minutes and 14 seconds less than 365.25 days. In the case of the Earth, there is no reason to set an integer relationship between the number of rotations the planet makes and how many of those add up to a year. This is why we need leap year. The shift of daylight by the mechanism you’re talking about simply adds into our timing systems, which are totally independent from the period of the solar cycle. We have an agreed-upon ‘day long’ increment that we measure using atomic clocks and then we shift our calendars as necessary to correct for the drift of these ‘day’ increments against the non-integral period of the year.

One thing that does flip by 180 degrees every half year is the star constellations visible in the sky at night. Gee, I wonder why that is…

>14. The South pole has a ceremonial pole and you cannot go past there and are not allowed to visit it. You should never question as to why.

This is kind of an excessively stupid point, even for the quality of points on this list. I don’t understand why you left it freestanding. Don’t ya know: it’s the Man lording it over, keeping you from your right to visit the south pole, whenever you feel the urge to just hop on your skateboard and flip an Ollie.

>15. The oldest treaty in the world is the antarctic treaty of 1959, the same year NASA was started. The treaty prevents anyone from going to Antarctica without government approval from one of the treaty signers.

Something tells me you aren’t that familiar with international politics if you think a treaty signed in 1959 is the oldest in the world. Maybe this treaty exists because the Antarctic is such a difficult place to travel to and live in that it’s hard for anybody to just up and go. Did you ever wonder why it wasn’t until the 20th century that governments even bothered to decide who could lay claim to the Antarctic at all? If it were an issue of walking across the street, maybe you could visit. So, talk to Elon Musk and ask him to build you a hotel. Otherwise, pretty much the only entities that can afford to go and stay in Antarctica and pack in and out the food, water and expendables necessary to survive there are governments. If you use their facilities, you work within their rules.

Yeah, kind of snarky, but what can I say. These people do sometimes bring it out of me.

This sort of comment has a way of riling me up because it is incredibly clear that the person writing it has basically no idea what they’re talking about, yet they are smugly certain that they have the truth of it, as if his little observations should blow my mind. As a general note, if you have a C- to D+ understanding of the world around you, there is usually a passing good chance that anything you think you intuitively know is probably false. Paraphrasing Neil deGrasse Tyson, Nature is under no obligation to humanity to be easily understandable.