For centuries people have wanted to lift themselves off our planet’s crust. Watching birds fly, humans regretted not having wings. There are many examples of human attempts to take flight; some with miserable results, and some that resulted in actual tools that now move through the air. We take it for granted, but so far we can only fly in the atmosphere where there is enough density to lift the craft. Bernoulli and Venturi helped the development of aircraft come along with the principles that are behind lift and speed.
Bernoulli's Principle supports flying by airplanes and sailing by sailboats, Venturi’s slot effect causes an increase in their speed. This is how air is used to propel these vessels. You can find enough about this stuff, but here are short explanations:
Bernoulli's Principle states that faster moving air has low air pressure and slower moving air has high air pressure. Air pressure is the amount of pressure, or "push", air particles exert. It is this principle that helps us understand how airplanes produce lift and stay aloft. Your paper airplane is thus able to take off and move in the air for a short while, when air pressure is diminished due to the air moving faster over this object. Of course, a source of constant propulsion is required. Otherwise the aircraft could not cause air to move faster over its wings.
Venturi’s slat re-directs the airflow at the front of the wing, allowing it to flow more smoothly over the upper surface when at a high angle of attack. This allows the wing to be operated effectively at the higher angles required to produce more lift.
So, people managed to get into the air, and fly like birds. However, it’s never enough. The desire to fly even further exists. The problem is that the air that is required for lift, exists within, but not outside the Earth’s confines. Besides providing air, the Earth is surrounded by plasma capsules that protect it from unwanted radiation, such as UV, and from so-called ‘sun flares,’ and who-knows-what-else… weird bacteria and such?
You could very well consider these plasma capsules the roof of our house. They are designed with great finesse, and without them we would not be able to survive on Earth. What to do, then, if you want to fly even further than an airplane can take you?
Get rid of the plasma layers
You demolish the roof of humanity’s home.
Now you are free to go whenever and wherever. But it is not without consequences for life on Earth.