How to increase air density on a planet?

The question is about what changes would have to be made to an Earth-like planet, in order to increase the density of air and hence make lifting gases more effective. If that is scientifically possible at all, that is.

Examples of lifting gases with capacity at Earth-sea-level:

• Helium with a lifting capacity of approx. 1.1145kg per m3
• Hydrogen with a lifting capacity of approx. 1.203kg per m3

Addendum:

Earth-like means that extreme changes in climate and/or composition of the planet are out of scope, as they would presumably make it impossible for most of our Earth flora and fauna to exist. Rather I am looking for changes that go in symbiosis with our own eco system (e.g. the fact that air on Earth-sea-level is more dense than in the Earth-Himalayas)

posted almost 9 years ago

dot_Sp0T‭

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