January 19, 2025

Coherence

4 minutes

Coherence-0.mp3

Coherence-0.mp4

Coherence-I.mp3

Coherence-I.mp4

Coherence-Interlude-Reprise.mp3

Coherence-Unplugged-Underground-XIII.mp3

Coherence-Unplugged-Underground-XIII.mp4

Coherence-Unplugged.mp3

Coherence-Unplugged.mp4

Coherence-intro.mp3

[Intro]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Verse 1]

The eye of I

(With a laser focus)

Can see to we

(Encompass us)

[Chorus]

Coherence

(Stay concentrated)

Coherence

(Say articulated)

[Bridge]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Verse 2]

Is it just a phase

(We’re going through)

Or, can we raise (raise, raise)

(And get into…)

[Chorus]

Coherence

(Stay concentrated)

Coherence

(Say articulated)

[Bridge]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Outro]

Our long distance relationship

Has set sail

A SCIENCE NOTE

A laser can start a fire similarly to a magnifying glass but through a different mechanism. Here’s how a laser focuses light and how it can ignite a material:

How a Laser Focuses Light

Monochromatic Light:

A laser emits light at a single wavelength (color), unlike sunlight, which contains multiple wavelengths. This makes laser light monochromatic.

Coherence:

Laser light is coherent, meaning the light waves are in phase and move together in a precise direction. This coherence prevents the light from spreading out and allows it to stay concentrated over long distances.

Collimation:

Laser beams are highly collimated, meaning the light rays travel nearly parallel to each other. This minimizes divergence and ensures the beam remains focused.

Focusing Lens:

To ignite a material, a lens or focusing element can concentrate the laser beam into a small spot. This increases the energy density (power per unit area) at the focal point, similar to how a magnifying glass focuses sunlight.

How Lasers Start Fires

Energy Intensity:

A laser delivers energy in the form of light to a material. The focused spot has a high power density (measured in watts per square millimeter or centimeter).

For example, a 1-watt laser focused on a spot 1 mm² can deliver 1 watt per square millimeter—much higher than the diffuse energy of sunlight.

Material Absorption:

The material must absorb the laser light. Dark, rough materials absorb more energy and heat up faster, just like with a magnifying glass.

Lasers tuned to certain wavelengths can target specific materials. For example, a CO₂ laser emits infrared light, which is highly absorbed by organic materials like wood or paper.

Heating to Ignition:

As the material absorbs energy, its temperature rises. If it reaches its ignition temperature, it combusts, starting a fire.

Key Differences Between a Laser and a Magnifying Glass

Feature

Laser

Magnifying Glass

Light Type

Monochromatic, coherent

Multicolored (sunlight), incoherent

Focusing Mechanism

Optical lens narrows the laser beam

Convex lens concentrates sunlight

Power Source

Requires an external power supply

Relies on natural sunlight

Energy Density

Extremely high in a small area

Moderate, depends on lens size and sun

Wavelength Control

Specific, can target certain materials

Broad spectrum, no specific targeting

From the album “Trapped” by Daniel

The Human Induced Climate Change Experiment

MegaEpix Enormous

...more

View all episodes

January 19, 2025

Coherence

4 minutes

Coherence-0.mp3

Coherence-0.mp4

Coherence-I.mp3

Coherence-I.mp4

Coherence-Interlude-Reprise.mp3

Coherence-Unplugged-Underground-XIII.mp3

Coherence-Unplugged-Underground-XIII.mp4

Coherence-Unplugged.mp3

Coherence-Unplugged.mp4

Coherence-intro.mp3

[Intro]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Verse 1]

The eye of I

(With a laser focus)

Can see to we

(Encompass us)

[Chorus]

Coherence

(Stay concentrated)

Coherence

(Say articulated)

[Bridge]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Verse 2]

Is it just a phase

(We’re going through)

Or, can we raise (raise, raise)

(And get into…)

[Chorus]

Coherence

(Stay concentrated)

Coherence

(Say articulated)

[Bridge]

In phase…

(We move together)

Together in a precise direction

Through haze

(In spite of whether)

Together, in phase perfection

[Outro]

Our long distance relationship

Has set sail

A SCIENCE NOTE

A laser can start a fire similarly to a magnifying glass but through a different mechanism. Here’s how a laser focuses light and how it can ignite a material:

How a Laser Focuses Light

Monochromatic Light:

A laser emits light at a single wavelength (color), unlike sunlight, which contains multiple wavelengths. This makes laser light monochromatic.

Coherence:

Collimation:

Laser beams are highly collimated, meaning the light rays travel nearly parallel to each other. This minimizes divergence and ensures the beam remains focused.

Focusing Lens:

How Lasers Start Fires

Energy Intensity:

A laser delivers energy in the form of light to a material. The focused spot has a high power density (measured in watts per square millimeter or centimeter).

For example, a 1-watt laser focused on a spot 1 mm² can deliver 1 watt per square millimeter—much higher than the diffuse energy of sunlight.

Material Absorption:

The material must absorb the laser light. Dark, rough materials absorb more energy and heat up faster, just like with a magnifying glass.

Lasers tuned to certain wavelengths can target specific materials. For example, a CO₂ laser emits infrared light, which is highly absorbed by organic materials like wood or paper.

Heating to Ignition:

As the material absorbs energy, its temperature rises. If it reaches its ignition temperature, it combusts, starting a fire.

Key Differences Between a Laser and a Magnifying Glass

Feature

Laser

Magnifying Glass

Light Type

Monochromatic, coherent

Multicolored (sunlight), incoherent

Focusing Mechanism

Optical lens narrows the laser beam

Convex lens concentrates sunlight

Power Source

Requires an external power supply

Relies on natural sunlight

Energy Density

Extremely high in a small area

Moderate, depends on lens size and sun

Wavelength Control

Specific, can target certain materials

Broad spectrum, no specific targeting

From the album “Trapped” by Daniel

The Human Induced Climate Change Experiment

MegaEpix Enormous

...more

Share Coherence

Sign up to save your podcasts

Coherence

Coherence