Wikipedia:Reference desk/Archives/Science/2014 October 23

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October 23

Time versus space

Two questions that I've wondered about for a long time:

1. Which scale is bigger, time or size?

2. Which scale is bigger, the size of a human to the universe, or from the size of a human to the teeniest object?

Many thanks for any opinions you can offer. Anna Frodesiak (talk) 14:08, 23 October 2014 (UTC)

2. It depends on what you mean. I'm guessing you are probably interested in mass, length, or volume. See Orders_of_magnitude_(mass), Orders_of_magnitude_(length), and Orders_of_magnitude_(volume) for some info. The other question is whether you want an absolute comparison, or in terms of ratios, e.g. on a logarithmic scale. For example, using mass, we could say that a photon is about 10^-40 kg, a human is around 10^2 kg, and the observable universe is about 10^52 kg. So on a log scale, there are about 42 orders of magnitude between a human and a photon, and about 50 between a human and the universe. This means we're closer in mass to photons. On an absolute scale, 100 kg is FAR closer to ~0 kg than it is to 10^52 kg, because to get from 100 to near zero, you just have to subtract a little less than 100. But to get from 100 to 10^52, you have to add 1000...000 (1 with 52 zeros)! This also means that we're closer to photons on a linear scale of mass, but much more so than on the log scale. Playing around with mass, vol, etc, and deciding what you mean by 'teeniest object', you can get several different answers on log and linear scales. SemanticMantis (talk) 15:12, 23 October 2014 (UTC)

I should note that, on absolute scales, humans will almost always be closer to teeny things than to to the universe. But on logarithmic scales, sometimes we are "closer" to huge objects. For example in length, the observable universe is ~10^26m by one estimate, and the Planck length is 10^-35m. So on a log scale of length, we are closer to the length universe than the smallest length, but on a linear scale, we are still much closer to the smallest length. SemanticMantis (talk) 15:20, 23 October 2014 (UTC)

1. You can't compare things that are expressed in different units. So this is like asking "How long (in meters) is 12 seconds?" - the only means for comparison is if you pick a particular velocity. A common choice might be the speed of light. Then you might ask whether the universe is spatially larger than the distance light could travel in the time since the big bang. That's kinda comparing the size of the universe to it's age in a kinda-sorta-quasi-reasonably manner. In that respect, the answer is "Yes". The universe is known to be at least 46 billion light years across - and it's thought to be around 13 billion years old. So using the speed of light as a means for comparison, I suppose you could say that the size of the universe is "bigger" than it's age...but it's really kinda meaningless. But as you phrased it, you're asking an even more abstract question about the relative size of the scales - and that truly is a meaningless question. You can't compare seconds to meters in the same way you can compare inches to kilometers...it just doesn't mean anything.
2. The universe is known to be at least 46 billion light years across...that's how much we can see. It may very well be infinite. But taking just what we can see...that's 4×10²⁶ meters - and for a two-meter human (basketball-player!) 2x10²⁶ times bigger than a human being. So how big is the teeniest object? Well, now it gets tricky. Things like electrons and photons, quarks and the like are thought to have literally zero size. So does the singularity at the center of a black hole. So humans are infinitely larger than those things - and if the universe is infinitely large then the ratio of universe-to-human is infinity and the ratio of human-to-quark is also infinity - so the answer is "exactly the same". If the universe is finite, then the ratio of universe-to-human is a big number, but it's not infinite, so human-to-quark is larger. But even that is kinda tricky. There is a thing called "the plank length" - which is the shortest distance we could ever possibly measure. A proton is 10²⁰ plank-lengths in diameter...and a human is about 3x10³⁵ plank lengths tall. So perhaps we could stretch a point here and say that the size of a human compared to the smallest distance we could ever possibly measure is 3x10³⁵ and the part of the universe that we can actually measure (which could be all that there is) is 2x10²⁶ times bigger than a human...which means that the answer comes out the other way around. But if the universe is much, much bigger than the part of it we can see and measure - then maybe it's not.

So to summarize: Your first question is meaningless (but if we really try hard and bend science to the breaking point, the answer is "distance")...and your second question is either (a) the universe is bigger...or...(b) humans are bigger...or (c) they are exactly the same...depending on how big the universe is (we don't know) or how you define "smallest" (you get to choose!).

Neither answer is very satisfying...so I'd have to come down on the side of both questions being essentially meaningless!

Sorry!

SteveBaker (talk) 15:34, 23 October 2014 (UTC)

... just to try to add to the excellent answers above, and extend the answers to time ... the smallest theoretically measurable time is about 5x10^-44 seconds (that's less than a millionth of a millionth of a millionth of a millionth of a millionth of a millionth of a millionth of a second, and we don't yet know how to measure such short times). On a base ten "order of magnitude" scale as used above, few humans live longer than 3x10⁹ seconds (100 years), and this is much closer to the age of the universe 4x10¹⁷ seconds (less than 14 billion years) than to the shortest measurable time. As Steve points out, the answers don't really mean much. Dbfirs 15:53, 23 October 2014 (UTC)

Just to spell it out a little more, you're saying that if we started with the human life span of 100 years, we'd have to move a decimal point about 35 places to get to the shortest time, but we'd have to move the decimal point only 8 places to get to the age of the universe. So a human life is "closer" to the age of the universe than the shortest time in this sense, which is using a logarithmic scale of "moving decimal places". But in an absolute or linear sense, 100 years is only about 100 years away from 10^-42 years (which is almost zero), while it is almost 14 billion years from the age of the universe. So of course our life span is much closer to the smallest time than to the age of the universe in an absolute sense. I know many of us know the distinction, but I recall OP expressing difficulty with numbers in the past, so I wanted to explain it again. SemanticMantis (talk) 16:40, 23 October 2014 (UTC)

Grace Hopper used to hand out 11.8 inch long pieces of wires at her lectures and call them "nanoseconds"; being one nano-light-second long, they represented the maximum distance a signal could propagate in one nanosecond in a vacuum. The speed of light, c, is being used there to convert between distance and time, and in some branches of physics it is useful to use c as a dimensionless constant with value 1 by measuring distance and time in the same units. (Our Planck units and geometrized unit system articles touch on this, but while these article talk about Planck length and Planck time, I recall that some general relativists I knew went around measuring time in units of centimeters. My memory may be faulty here, so I'd appreciate if someone active in the field could chip in. @BenRG: Are you here?) In any case, while this does not speak to which of time or space is larger, it does show that the units of time that humans natively work with (such seconds and years) are much, much larger than distances that humans natively work with (such as centimeters, meters, and kilometers), because the speed of light, which, in some circumstances, can be considered the conversion factor between the two, is much, much faster than speeds that humans natively work with. -- ToE 16:59, 23 October 2014 (UTC)

Yes, the convention in general relativity is to set G=c=1 and use length units for everything. Geometrized unit system is the article. -- BenRG (talk) 17:41, 23 October 2014 (UTC)

Thank you so much all! That was amazing and I understood 99% of it, (and that is saying a lot considering I only understand around 10% of the reason paper appears half size when after being folded in half). You should all really teach this stuff because my teachers could never explain anything so well. By the way, who is who is "OP" in '"...recall OP expressing difficulty..."? Anna Frodesiak (talk) 02:48, 24 October 2014 (UTC)

To bad noone made clear that today human science neither knows the age of the universe nor does it know its real size. Even an respected astrophysics educated guess is still only a guess and worse its obviously limited on what is visible to us with help of current technology. --Kharon (talk) 03:49, 24 October 2014 (UTC)

It's the nature of science that theories are based on available evidence. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:51, 24 October 2014 (UTC)

This is no science! You could highout call astrophysics theoretical imaginations an educated guess. --Kharon (talk) 03:59, 24 October 2014 (UTC)

"OP" means "Original poster"...the person who asked the question...which in this case is you.

The folded paper thing...yeah...when you fold a piece of 'A/B/C' series paper (A4, A3, etc) in half, you get a piece of paper that's the same shape as the piece that you started with. That only works with paper where the length of the long sides is 1.4142 times that of the short side. If you're a paper maker, that's a handy property because you can take a pile of A3 paper and chop it down the middle to make a bigger pile of A4, then chop that in half to get A5 and so forth - and there is never any waste! In fact, you make your paper in A1 sheets, then cut it to make A2, A3, A4, A5 and so on. American paper sizes (letter, legal, etc) and some older UK sizes (eg foolscap) are just a mess - they don't have that cool folding property because that 1.4142 ratio isn't followed. This must drive paper makers crazy...they either have to have a different machine for making letter and legal sized paper - or they have to generate a bunch of waste when the cut the sheets down to size. The significance of this 1.4142 number is that 1.4142 x 1.4142 = 2.0. (Actually, the number isn't really 1.4142 - it's a number that goes on forever without repeating, like pi. But typing infinite strings of numbers hurts my hands - so I'm rounding it off to 1.4142).

To understand why that number is important requires a little algebra. If you take a sheet of A4 and call the length of the long side 'a' and the length of the short side 'b' - then we could say that a/b is the mystery number 'x' (which we'd like to prove has to be 1.4142). You can write a/b=x.

If you fold the A4 paper in two to get a sheet of A5, then what was the short side becomes the new long side and half of the old long side becomes the new short side. So now the long side has length 'b' and the short side is 'a/2' - and b/(a/2) must also equal 'x' if the paper has the same shape. So algebraically, now we know that:

  a / b = x         (1)
  b / ( a/2 ) = x   (2)

Taking that second equation and shuffling it around a bit, we get:

  2.b / a = x

...which means that we get:

  a / b = 2 / x

...but we already know from equation (1) that a/b = x, so we can say that to have this neat folding property, a/b = x and also a/b = 2/x. Which in turn means that:

  x = 2 / x

...which we can rearrange to:

  x.x = 2

...and we know that 1.4142 times 1.4142 equals 2, so x does indeed have to be 1.4142 - and that's why paper is designed that way.

Sadly, it's not so easy to understand this kind of argument without getting your head around the algebra.

SteveBaker (talk) 04:43, 24 October 2014 (UTC)

OP, ok, I get it.

Actually, I was sort of kidding about the paper, but now that I've read your explanation, it is pretty interesting. As for the maths, even though it looks simple, I just never get it. That part of my brain never developed, and is probably the size of a grain of sand.

What you wrote about rounding off is interesting. Somebody explained the idea of base 12, and how we would have used that if we all had 12 fingers and then maths would be easier. I wonder if other planets use base 12. My friend say there's no way we could convert, and even if we colonized a new planet and fresh-started with it there, base 12 would make it hard to communicate. Maybe there could be software in between. Anna Frodesiak (talk) 05:03, 24 October 2014 (UTC)

Translating between different bases is something computer scientists do all the time - computers count in base 2, and because that makes for long numbers of zeroes and ones, computer scientists often use base 16 (which has the property that every base-16 digit can be neatly converted to 4 binary digits and back again). This really will not be a problem for communication, except maybe when space tourists try to read alien menus (better check the numbers of fingers of the waiter - if it's three per hand, you can splurge, but if it's 8, better stick to items that have at most two-digit prices). --Stephan Schulz (talk) 07:28, 24 October 2014 (UTC)

It's worth noting that the number Steve Baker is referring to as 1.4142 (properly called the square root of 2) will have an infinite number of decimal places in any base you choose, since it's an irrational number (which basically means it cannot be stated as x/y, where x and y are both integers ("whole numbers")) MChesterMC (talk) 08:24, 24 October 2014 (UTC)

Fair enough. Many thanks. :) :) :) Anna Frodesiak (talk) 09:10, 24 October 2014 (UTC)

Yeah - working in different number bases isn't that hard - it's just a matter of practice. I'm a computer programmer and I can do base-16 math ("hexadecimal") in my head, just about as easily as in base 10. Higher bases like 12 do have some convenience issues - memorizing the multiplication tables is one of them.

But, believe it or not, you probably work in base 12 all the time! I grew up in the UK, with pre-decimal currency (12 pennies in a shilling) and we still have 12 inches in a foot - so base 12 arithmetic is actually in use all of the time. You don't think of it like this - but every time you say "3 feet, 6 inches", you're really saying "36" in base 12 and it takes mental effort to convert that to 42 inches (base 10). Every time you go between inches and feet-and-inches, you're doing a conversion from base 10 to base 12 - and vice-versa. Base 12 is (in some respects) more convenient than base 10 because 12 is evenly divisible by 1,2,3,4 and 6 - where base 10 is only divisible by 1,2 and 5. So there are some benefits to be had with base 12.

Base 16 is convenient for computer programmers because our machines are really working in base 2 (which is crazily inconvenient for us humans) - and it's very easy to mentally convert back and forth between base 2 and base 16 - but more effort to convert back and forth to base 10.

It's interesting to note that the ancient Sumarians used base 60, which is (in some respects) even more convenient than base 12 (it's evenly divisible by 1,2,3,4,5,6,10,12,15,20 and 30!) - but doing multiplication - or even addition - directly in base 60 is painful. Traces of that Sumarian base-60 system linger to the present day in our hours, minutes and seconds system for measuring time. 5 hours, 8 minutes and 4 seconds is 584 seconds in base 60.

Also, nobody has an underdeveloped math brain. You can always get better by learning and practicing...it's like exercising a muscle. If math interests you, keep pursuing stuff like this and it'll get easier. SteveBaker (talk) 20:05, 24 October 2014 (UTC)

That is so interesting! I never thought of feet and inches as base 12 before. Of course! I've emailed this last bit to a bunch of friends. I hope that is okay. And the lingering base 60, also very cool. Thank you!

And it is not that I don't like maths, it is just that it's a bit like magic to me, probably like when a dog goes in an elevator and the doors open and he's in a different place. Wonderful but only a vague idea how it all happened. :) Thank you again, my friend. Anna Frodesiak (talk) 23:38, 24 October 2014 (UTC)

Heroin Addict -vs- Varicose Vein

In the spirit of the irresistible force vs. the immovable object... Varicose veins seem relatively hard to treat well, requiring quite harsh methods that seem always to have some risk of stroke or other thrombosis. But intravenous drug users notoriously manage to destroy every single (surface!) vein in their entire body, until they get truly weird things like localized gangrene of the penis from unusual injection sites. While no one would suggest their practices are safe, it strikes me that to remove that many veins with even a fraction of a percent chance of stroke each time, would lead to a much higher rate of devastating trouble for drug addicts than is usually reported. So I'm scratching my head, wondering...

a) Do heroin addicts with varicose veins find them to be a secret weapon that lets them inject a huge number of times without going away? or

b) Do heroin addicts with their repeated pricks manage to destroy veins more effectively than known surgical treatments?

Or something else...? N.B. no, not a heroin addict, so this isn't medical advice. ;) Wnt (talk) 19:53, 23 October 2014 (UTC)

I haven't seen the Venn diagram of heroin users and varicose veins but I imagine it's quite small. Heroin addicts with the level of damage you describe don't tend to live long. I'd also suspect that the lack of return flow from varicose veins or any type of phlebitis is not conducive for drug use. --DHeyward (talk) 11:30, 24 October 2014 (UTC)

From the chart in Perter Laurie's book ( Drugs: Medical, Psychological, and Social Facts; page 146 fig. 4) the second peak in heroin addicts is at age 38. From then, the incidence of addiction falls off fall (and that is not due mainly to mortality). Varicose veins usually don't develop until well after this age. Second, their are very effective chemical treatments for collapsing veins. Third, it is adulterated street heroin that collapses veins not the heroin itself. Back in more enlighten times, when addition was considered an illness not a crime, addicts could receive good pharmaceutical grade morphine sulfate (heroin). That, together with clean needles and sterile hypodermic syringes avoided most common medical complications setting in. Finally. It is not the availability of easily accessible veins that regulates the amount of heroin injected but rather the degree of the untreated addiction. Don't know if that answers your questions.--Aspro (talk) 13:29, 24 October 2014 (UTC)

I thought of some of these things, but am skeptical. To begin with, I'm sure there must be a fair number of people in the Venn intersection; what matters is not whether they're the majority but only whether they happen. Also, our article collapsed vein doesn't cite impure drugs as the reason; this was my impression, distorted no doubt by media portrayals like The Knick - it would be very interesting to see some historical account of pre-Prohibition intravenous drug users. (Indeed, the hypodermic syringe was invented in the 19th century) As for the lack of return flow, I'll agree that is quite plausible, though I wonder if the addict could get around that simply by stroking the veins upward after injection (I have no idea). Wnt (talk) 16:02, 24 October 2014 (UTC)

If this article doesn't mention the adulterants that collapses veins, then this is an oversight. WP is an encyclopedia that is work in progress. Second: Pre-prohibition-drug-use was not news back then, so apart from some anecdotal references, I should not think that there is any really good studies that give a true picture. Third: Although a varicose veins may be swollen, the blood in still flowing. It is just that varicose veins allow some back-flow of the blood on its journey back towards the heart. Yet get back to the heart it goes ---(dead people with no functioning circulation don't inject drugs). So with releasing the tourniquet, the stroking of the vein is not necessary to experience the 'rush' or in layman's term 'the opiate orgasm'. Once the opiate enrich blood, gets back to the heart, some of it is pumped straight into the cranial artilleries and across the blood brain barrier and into the brain. There, it quickly finds its way to the opioid receptors creating the sensation of a rush. No stroking need be involved (this is not to be confused with smacking the vein to bring it up).--Aspro (talk) 13:40, 26 October 2014 (UTC)

Well, I couldn't swear without hearing direct reports from addicts that there wouldn't be a slower onset due to a more sluggish blood flow, but generally, that sounds like it ought to make sense. But I'd still like to see sources about the adulterants, since there's no a priori reason I'd see why puncturing veins enough times couldn't make them collapse in and of itself. Wnt (talk) 03:09, 27 October 2014 (UTC)

Dot on the sun

Minneapolis photo at the height of the eclipse. Wnt (talk) 16:20, 24 October 2014 (UTC)

I just looked at the solar eclipse (with 2 pairs of welding goggles plus a CD) and there was a small black dot on it, about in the middle, a little below the sun's equator. What was that? Ariel. (talk) 22:25, 23 October 2014 (UTC)

It's a sunspot. Did it look like this, by any chance? --Bowlhover (talk) 22:27, 23 October 2014 (UTC)

There was just one dot that I could see. Is there one main sunspot right now? It was a perfect circle, I thought sunspots more more patchy and diffuse. Ariel. (talk) 22:35, 23 October 2014 (UTC)

It didn't look like today's sunspot photo but the position was exactly right, so I guess that's it was. Thanks. Hope you guys got to see it. Ariel. (talk) 22:47, 23 October 2014 (UTC)

You should think yourself very lucky. The last total eclipse in the UK was in 1999 - visible in the south west. Big build up beforehand - tee shirts and eclipse glasses on sale, hotels sold out etc. Big day arrives and it's cloudy all day and hardly anybody sees anything of the total eclipse (in the north we saw a partial). Next one due in 2090... Richerman (talk) 23:12, 23 October 2014 (UTC)

That's my soul up there! --Jayron32 02:12, 24 October 2014 (UTC)

Solar cycle#Surface magnetism. --Kharon (talk) 03:54, 24 October 2014 (UTC)

I was also watching through welding goggles (the Darth Vader look is kinda cool too!) - and I knew that the splotch was a sunspot, it looked round to me too - and I suspect that's due to some optical property of the welding goggle glass.

A cooler way to watch solar activity is to cover a sunny window with tinfoil to block out all of the light - then punch a pinhole in it. Darken the room completely, then take a large sheet of paper and place it in the way of the sunlight flowing in from the window. The image projected onto the paper is HUGE and comfortably dim. If it's too dim, you can slightly enlarge the pinhole, but if you make it too big, you'll get a blurry image. Anyway, with a setup like that, you can watch sunspots any time you like...the sun is interesting to watch even when there isn't an eclipse. SteveBaker (talk) 04:55, 24 October 2014 (UTC)

For general interest: that Sunspot group is currently very active, so there's a distinct chance we'll be hit by a Geomagnetic storm anytime in the next couple of days. {The poster formerly known as 87.81.230.195} 212.95.237.92 (talk) 13:19, 24 October 2014 (UTC)

There's a "NASA photo stream" on Flickr (?!) [1]. The interesting bit to me is whether or not we can see the dot rotating with the sun. From [2] I see only the most minimal amount of rotation in a single eclipse, but, the photo stream I cite involves shots from multiple locations. I'm actually not that clear on how long this eclipse ( see Template:Solar eclipse set 2011-2014) or any solar eclipse actually takes to pass along the entire length of its route. Wnt (talk) 16:20, 24 October 2014 (UTC)

The sun takes 25 days to spin once on it's axis - so over the few hours of the eclipse, you wouldn't expect to see much change in the position of the sunspot. The sun is far enough away that photos from different places (or times) won't show much difference either. The moon's shadow crosses the Earth at 1700 kilometers per hour - and only covers one place on the earth for at most seven and a half minutes. Since the circumference of the Earth is only 40,000km - I'd expect the eclipse duration to be no more than about 10 hours - but it's tough to come up with more exact numbers. But the sunspot won't move much, even over that length of time. SteveBaker (talk) 19:45, 24 October 2014 (UTC)

ClearVUE Television Antenna vs. the expensive ones on Radio Shack's website

My mother lives in a condo on the second floor and has limited television options (Comcast or over-the-air). She's getting a weak signal from WINK-TV, WFTX-TV, and WZVN-TV, and she was asking me about signal amplifiers. Of course, I knew that the ClearVUE antenna she has already amplifies the signal, and I was wondering if there would be any advantage to adding additional amplifiers or getting a different antenna. Any advice? 71.52.178.42 (talk) 22:49, 23 October 2014 (UTC)

Signal amplifiers are not very useful for poor signals (they amplify the noise and the signal at the same time), and two certainly isn't valuable. They are used to amplify the signal before a long cable run, or to use the signal with electronics. But if your SNR is poor (a weak station) they don't help. Instead you will want a better antenna.

What kind does she have? And what directions do the signals come in? Check here. All from one direction? Or all around? You can make a surprisingly good directional antenna yourself if you google "coat hanger antenna". Ariel. (talk) 22:42, 23 October 2014 (UTC)

She has this kind of antenna. She also has a Samsung Smart TV (a big reason she doesn't want Comcast is because she doesn't see the value in having it, being that she has Netflix and Hulu Plus + a decent CenturyLink internet connection). 71.52.178.42 (talk) 22:48, 23 October 2014 (UTC) Add: Interestingly enough, the two stations that come in the best are the two that say she needs a "red" or "violet" antenna according to the website you provided. Don't know what that means. 71.52.178.42 (talk) 22:55, 23 October 2014 (UTC)

First, the ClearVue antenna your Mom's using, http://besthdtvantenna.net/clearvue-digital-tv-super-booster-indoor-tvfm-antenna isn't really a TV antenna.

It's a signal rectifier that tries to pass radio waves from the wiring in your Mom's condo to her TV tuner. That works surprisingly well sometimes (she's pulling in distant TV stations, according to you) but not for the stations she'd like to watch in her area, apparently. Not really a surprise, because condominiums aren't generally wired to provide good TV reception through their electrical wiring.

Without breaking the bank and going to Radio Shack, it might be worth going to your local discount store (cheaper than Wal-Mart or Target, they're both trying to beat $40 out of their customers for so-so antennas) and just getting the cheapest thing you can find that has both "rabbit-ear" and "wire-loop" antennas on it. If you can't find anything cheaper than $20, then suck it up and get a $20-$40 special from Wal-Mart or Target.

But make sure that your antenna has both rabbit-ear stick antennas and a wire-loop antenna on it. Those rectangular plastic antennas just hide essentially that same stuff inside a pretty plastic box, but I find they're not as good as external rabbit ears and a wire loop. Reason? At least one of the stations you mentioned getting poor reception on, WINK-TV, transmits its signal on UHF. So without the wire loop, you won't be catching that one. I'm at a loss for why your Mom's not getting WFTX well, it's low-end VHF and ought to be easy to catch on any antenna setup that gets distant channels the way you say she does. But local electrical noise, including older computers and wi-fi routers, could be interfering with that channel. Or your Mom might live right next to WFTX's antenna, and the amplified signal from her condo's wiring could be overloading the TV tuner - that sometimes happens. Who knows?

Don't buy an amplified antenna until you've bought a cheap rabbit ears and wire loop antenna and tried tuning in to the TV channel you have the worst luck with, then placing the antenna as high as you can (mine's on top of my bookcase) and turning it slowly until a good picture and sound appear on the TV. That ought to solve the problems you have with the other two channels, too. I'm getting all the "green" channels on MY antennaweb.org map with a rabbit ears and loop antenna that cost us $5. So try that, first, then if you lose the distant channels your Mom was getting before, get an amplified rabbit ear and loop antenna.

I'm betting that cheap non-amplified antenna will catch the channels that your Mom's "plug-into-the-power-plug" antenna won't.

Good luck! loupgarous (talk) 11:04, 26 October 2014 (UTC)

• Can I take it that you mentioned 'condo' because its one of those condos whose lease does not allow external aerials? Does her block have a Residents' association that can force the owners to install a communal aerial [3] in the loft space, roof top etc. The owners must allow for a remedy for any prohibitions that they impose, which can be considered unduly restrictive. After all, your moms neighbours might suffer the same problem. Finally, have you knocked on their doors and found out their solutions - if any (and you can witness this proof on their TV's). If their solution works for them, then you won't have to take the financial risk of purchasing an antenna that still fails to pull in a good signal. Finally, it might seem obvious but some coax cables that one can buy are rubbish. If they are so bad that they attenuate the signal too much, then regardless of how good the antenna is, the signal won't get through. As others have said, you should not need an amplifier.--Aspro (talk) 21:10, 26 October 2014 (UTC)