My Day In A Few Words

The First Star


The universe is believed to be infinite in all directions. We reside within an observable universe, which is the spherical region around us that has had time for its light to reach us. This is expanding and it is called the particle horizon. As time passes, further regions have had time for their young light to reach us.

So you'd think over time we'd see more and more new light.

But there is another sphere, the Hubble Volume. This relates to the expansion of the universe. Objects beyond this range are actually receding from us at greater than the speed of light due to the expansion of space.

In an accelerating universe, which we believe ours to be, this volume will lag behind the particle horizon. What this means is that in actuality, the universe we can see is shrinking, at least in 'contents' as objects near the edge over take the Hubble Boundary. At that point, the light they emit at that time will (once it travels all the way back to earth) be the last we ever see of it. They will essentially disappear from our universe.

I believe this is already happening with the most distant possibly visible objects, although I am not certain we are actually able to see them with our technology.

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We Are More Open No Matter How Things Might Look


When I was young there was an understanding that you get married. You reached an age and got married, and then you had children.

That was how it was done. Gender roles helped shape this perspective.

People once perceived marriage as a "duty" though that is less today than it was before and want to "stay young" longer than before.

Birth control and the economy have changed that for many people now who get married later in life.

Back in the day before you could have kids in a socially acceptable manner you had to be married. And since birth control wasn't really a thing you generally had to be married to have sex so people got married so they could have sex with each other.

As birth control became a thing the age moved back a bit. And as college became the norm for women as well as men it pushed things back again further. And now with the economy being difficult and housing/wedding costs on the rise getting married can be financially stressful for a young couple.

Our grandparents likely could afford to get married, buy a house and afford children much earlier in life. Those days are long gone in the new global economy we have. But you still see remnants when you look around. The bridal shower before the wedding, baby showers that are held when the first child is on the way, and the way our culture perceives not owning a home are all remnants of this time.

There are also other factors:

  1. Premarital sex is less taboo.
  2. Birth Control/Abortion is available so less shotgun weddings.
  3. Less expectation/need for large families so there's less pressure on marrying early.
  4. More people are going to college/graduate school.
  5. Women are less tied economically to men now so they don't have to marry to provide for themselves anymore.

Combine that with the percentage of superior level of education among population has grown so, while my mother and dad could get married while they were 21 (high school and primary school level of education), I was still studying at university and couldn't marry before being 26. In facts is kinda hard to have a revenue that's enough to pay for studying and live and get a family while studying.

Escaping family roles, that once forced people into a model that was designed for "the husband to get a job, the wife care for the house and the children" the roles were kinda dependent one from the other. Nowadays males and females get a job and work and time for house-caring has become much less (washing machine, dishwasher, vacuum cleaner, etc), as much as time for shopping (think about superstores compared to the grocery and the butcher and the greengrocer and...) so "technically" marriage is less necessary than before and people worry about that later because either male or female are less dependent one from another.

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Practical Yet Functional


I watched a documentation about modern bottling and packing practices and they had an interesting segment on how bottles are actually designed.

An arch is a strong structure. Imagine taking an arch and spinning it around, you get a dome which is also a very strong structure. It's good at resisting forces from inside too.

A bottle with a dome can better resist pressure. Soda has pressure because the bubbles are CO2 gas which can dissolve in water, but getting enough into the water to make it fizzy takes cold and pressure. When you do get enough in there, it doesn't like to stay in the water. Keeping the water under a bit of pressure can help though. We have glass soda bottles without curved bottoms, so what's different? A curved bottom means the bottle can be thin, and it's easy to make.

Old plastic soda bottles had a plastic cap glued onto them so they could stand up with the curved bottom. But this is extra material and extra steps. I would also bet the old bottles were harder to recycle but they were phased out before I can recall recycling becoming the norm. I believe someone figure out the 5 pointed bottom would work well enough because we are not talking about crazy high pressures. I believe the bottom of these bottles are also a little thicker than the old ones. But the saving in materials, fewer manufacturing steps, and making them easier to recycle beat out the increases in price for the new process.

Interestingly enough, many of the "aesthetic" features on bottles are for functional purposes rather than looks. Carbonated soft drink (CSD) or Pop bottle bases (petaloid) are shaped this way because of the pressure in the bottle. The ideal base for a pressurized bottle would be a sphere, however this is not practical for keeping your pop upright, but if you ever look at packages such as a gel shaving cream dispenser you will notice that there is a cup fit onto the bottom of the bottle. This is because shaving cream requires even higher pressures and so Actually does have a spherical bottom and has a base insert that keeps it upright.

Another example of function rather than form in plastic packaging is sports drinks (anything ending in an "ade").these bottles are called hot fill meaning that they are.... ta da. Filled hot, so the inset panels that you see on these bottles are to accommodate the loss of pressure once the liquid cools down. These bottles start with the panels popped out and during filling they suck in.

There is a lot of interesting things about the plastic packaging world that many of us take for granted until we understand all that goes into it.

If you want to see the ability of a soda bottle to hold pressure in action, google "soda bottle water rocket" (my daughter loved watching the cute one with the bubbles added to the bottle contents). If your launchpad can fit the mouth of a water bottle, you can see how it behaves under pressure in contrast.

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Escape Velocity


Escape Velocity, which directly relates to this and might be useful. In style terms and such, and helps clarify what Escape Velocity actually is, and why Constant low speed is perfectly viable.

Heres a Link if you want to read it, though I will bring up the more related points.

Basically though, Think of a Helicopter, and how it can slowly rise into the air. As it is doing so, it is going to space at a slow speed. The problem is Helicopters work via air, and there is no air in space. However, If we had some way to keep the helicopter going, like say some rocket engines, and kept it going at that same speed, then indeed eventually it will go into space, and it will keep going. There is nothing wrong with this logic, for getting to space that is. The helicopter is accelerating upwards at a rate equal to or greater than gravity's pull downwards, allowing it to go up.

So, why do we do it at high speed. This is related to the explanation of Escape Velocity. Escape velocity of earth is ~11 km per second. This is the minimum speed you need to be traveling to go from earths surface to space where earths gravity is truly negligible. This is important, because if you go any less than that, and have no way to apply any more force to propel yourself away from earth, you will fall back to earth eventually. This would be just like throwing a ball in the air. Eventually, it comes back.

This is where Orbiting comes into play. Orbiting is simply constant freefall, but in a sideways direction at a speed great enough that as you fall to the planet, which is a sphere, the land will curve away at the same speed as you are approaching it. This is best known and shown from Newtons Cannonball animations. The orbiting object is constantly accelerating toward earth, but is also going sideways at such a speed that it misses. Because it is in space and there is almost nothing in space to cause friction, it never slows down the sideways direction, and because the planet is a sphere, the gravity that accelerates you on one side, slows you down on the other, and it all balances out.

So, why do we not just go up at a slow speed to go to space, because all that would happen is eventually we would fall back down. The great speed going up is simply to get up there faster, but is also helpful when it turns some of that up speed into sideways speed, allowing it to smoothly go into orbit. If the helicopter got into space, it would have to constantly expend fuel to keep up there. To stop spending fuel, it would either fall back down, or have to get going sideways fast enough that it reached orbit speed. Like getting from one corner of a square to another, the shortest route is not go to the top, then go sideways, but to cut through the middle in a diagonal path. Gravity forces it to become a curve instead of a straight diagonal though, but it is still significantly more efficient.

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My Daughter's Test Scores


My daughter was interested in how her test scores are calculated. And I sort of lied and gave her a more useful, yet advanced example. Here is what I told her.

Lets say you have 5 tests, and you got 60 70 80 90 and 100 on them, all out of 100. You have a total of 400 points, but the maximum you could get is 500 points, or 400/500. This means that your average, is 80%.

Now, your Professor was very generous, and is dropping your lowest grade. You now only have 4 graded tests, so the maximum is 400, and your test scores are 70 80 90 and 100. You now have 340 points out of 400 points. If we scale this up, it becomes 425/500, which is 85%

So, dropping your 60 point test drops the total points you could get from 500 to 400, and the points you got only drops 60. Because this is your lowest score, more complicated math basically dictates that there is no way the average can go in any direction but up. In this case, it raises your total percent by 5%, which can be significant.

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Smile It Can't Be That Bad


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I hate feeling sad, but it is an emotion like any other and I as a person experience it from time to time like you do.

Sometimes I don't want to hear your words of condolence, your sad face, what I want is a reassuring smile.

There is evidence that Smiling actually makes you happier, even if its a fake smile. The simple action of pretending to smile actually seems to somewhat alter you mood towards a mood that would make you smile. Apparently others happiness can also be contagious, at least if your not a scrooge. If someone is very happy/cheerful, it tends to make us happy as well, and I have heard dogs abuse this heavily.

if that is true, then the opposite would also be true. To be sad, and to be confronted with the sad "I'm sorry" face is a double whammy, Your probably thinking sad things, feeling sad, and seeing sad faces, so it makes sense that it could be overwhelming.

It would then also make sense that putting up an apathetic act would help suppress emotion. Whatever "mask" you put on, your actual feelings seem to try and follow.

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