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Comment Re:Time to travel 11 light years (Score 3, Interesting) 89

Let's see if I can work this out correctly;
First assume the spaceships weight negligibly different than the mass of the fuel. The thrust needed to push the weight at a steady 1g will be proportional to the mass of the ship at each interval of time. SO the rate of mass burn is proportional to the mass which means the mass is a decaying exponential.

M = Mo * exp( -g * time / thrust_to_weight )

If you think about this for a moment it becomes clear that any amount of mass would do since as the mass gets lighter it takes less fuel so the ship could go indefinitely at 1g. The problem is the assumption that the ship weighs nothing. so let's fix that.

dM/dt = -g*(M+Ms)/thrust_to_weight.

where Ms = mass of ship and M = mass of fuel.

I'm spacing on how to solve that equation so I'll approximate it by saying that until M = Ms we can mostly ignore the ship mass. therfore for a 6.6 year flight time the fuel required is about:

Mfuel = Ms * exp( g* (6.6 years)/thrust_to_weight )

Mfule = Ms * exp( +303,800,000/thrust_to_weight).

So you need a rather high thrust to weight ratio due to the coefficient in the exponetial.

Let the pillory for my "obvious" math errors begin!

Comment Time to travel 11 light years (Score 3, Interesting) 89

traveling with a 1G acceleration:
1/2g t^2 = 1/2*11*3E8

so t = 3.3 years to half way. 6.6 years to go all the way and thus 13.2 years for the round trip.

Thus you could easily go there and come back in your lifetime.

Note that this is also Faster than light can make the round trip. However that is not any violation of relativity. THe people on earth would have aged a lot more than 13.3 years during your trip. But you would only have aged 13.3 years.

Comment How to make a telephone solicitor mad (Score 4, Insightful) 251

Last century, I worked for a magazine sales company that did telephone soliciting. We loved it when people slammed down the phone because it meant no wasted time. The worst was when someone wanted to chat. One time a kid answered the phone and I asked for the dad. She said, "He's out in the garage under the car" and ran off to fetch him. It was a dillemma what to do next. Hang up? wait?. Another time the person on the other end kept repeating only the word yes during my sales pitch and then 5 minutes in switched to "can you please speak chinese". Even when I said "goodbye".

These days, I tell them I'm really glad they called and I need to move to the phone by the computer so I can purchase what they are selling. Then I set the phone down and go about what I was doing.

Comment Sony (Score 1) 116

Nah this is just Sony Electronics wanting to leverage their entertainment holdings to sell TVs and PLayers with proprietaty formats while Sony Entertainment wants to maximize sales. Or maybe I got it backward. Anyhow lots of diversified companies have internal conflicts. The IBM PC which uses all non-IBM parts was not made by the primary Computer division at IBM. Samsung also has internal competition with conflicting objectives,

Comment it's not the ads it's the surveillance. (Score 4, Insightful) 611

it's the surveillance I don't like. In theory this surveillance is supposed to get me relevant ads but it just creeps me out with it's persistence. I don't really need relevant ads ever. What I actually like is being exposed to lots of different ads. It gives me a sense of what the world is up to in a way. SO I don't mind the ads. It's not like TV ads that I have to wait through. they are just off to the side. What I don't want therefore is the surveillance. it has negative value to me. I don't want targeted ads.

If I could be sure I could be surveillance free I'd pay $230. But I don't see how that is possible. How would I know? where does one draw the line-- things like cookies for sessions and autologin on returning to a site and resuming my netflix movie where I left off are useful. What about amazon auto suggest? I once bought a book on amazon about sexual practices in different cultures and for months I had autosuggests for dildos and some amazingly raunchy bondage movies that I had no idea amazon carried. My sense of embarrassment prevented me from using amazon when other people were in the room. I think however this is not really the surveillance I am worried about. I can easily not use amazon and certainly in the future I always now check the "people who bought this also bought..." before I purchase some item that will trigger things I don't want it suggesting to me. SO that's containable.

But that experience makes me wonder what that little search did for my google profile. Am I now pegged as a dog fucker on google because the key terms I used for a scholarly search had other meanings? I know that google pricks up it's ears when a search leads down a path to a purchase.

You might ask why do I care. I just do, and that's normal. were trained in caring about appearances when were on the playground.

Comment Impact of humans (Score 4, Interesting) 116

If for somereason all the humans in NY city were to just up and leave there would be a huge biological impact. rats, cats, dogs, birds, trees, and butterflies would be disrupted by lack of food, changes in water, reduction of the temperature island, heated underground spaces, lack of trash. Predators formerly finding the human habitation uninviting would swarm into the area.

    Likewise formerly unfit mutants on some species, such as cockroaches in bright colors that were out in the daytime might appear

I'm somewhat skeptical that every observed change in Fukashima is casued by radition, even the new appearance of mutations. the departure of the human population might well be a catalyst as well.

Comment Rigged statistics. (Score 3, Interesting) 183

more people die in 1 month from the flu in africa (over 5 K from the last article i saw ) than they die from ebola last year.

But those people dieing of of the flue are often compromised in some other way, such as old age or malnutrition.

you might as well say that more people in africa die of old age every day than all ebola deaths combined.

The reason people fear ebola is that unlike old age, it spreads and attacks the healthy.

Unless you are literally playing in a sick persons bodily fluids, the risk is almost 0

the exact same exaggeration is true of flu. You catch flu by being in close proximity to someone with the flu or some a vector that can temporarily support the flu's transmission, just like ebola.

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