tunneling

In physics, the passage of a particle through a seemingly impassable energy barrier. Though a particle's energy may be too low to surmount a barrier in classical physics, the particle may still cross the barrier as a consequence of its quantum-mechanical wave properties. An important application of this phenomenon is in the operation of the scanning tunneling microscope.

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• Sexual penetration
• Market penetration, the degree to which a product or service is known and/or used
• Penetration (telecommunications)
• Penetration (firestop), an opening in a wall or floor assembly required to have a fire-resistance rating, for the purpose of accommodating the passage of a mechanical, electrical, or structural penetrant
• Penetration (warfare)
• Penetration (weapons), the ability to pierce the target's armor or other protection
• In magic, an illusion in which one object appears to pass through another
• In basketball, the ability of a player to drive through the opposing defense

Popular culture

• Penetration (artistic), An artistic strategy
• Penetration (band), a punk rock band
• "Penetration," a song on Pedro the Lion's album Control
• Penetration Recordings, a record label
• Body of Lies (film), an upcoming film formerly known as Penetration

See also

• Interpenetration