Skip to main content
Sandbox Physics

QUANTUM EVIDENCE / MAGNETIC MOMENT

Atomic Magnetic-Moment Comparator

Compare two ideal orbital–spin manifolds in the same magnetic field. Record state-selected atom counts, locate both resonances and separate the electron spin factor from a shared field drift.

Interactive modelAtomic Magnetic-Moment Comparator

Ideal state preparation → transverse RF interaction in a shared vertical field → state selection → atom counter. The second state selection is acquired sequentially on the same apparatus. No calculated deflection trajectories are shown.

OBSERVE / KEEP THE RECORD

Compare the two resonances.

At each coordinate: a state-selected count and a separate whole-beam reference for each branch. All four exposures are independent Poisson observations. Scan playback is accelerated.

Ready. Predict, then acquire.

STATE-SELECTED RATES / PER SECOND

A field shift or a factor shift?

Applied RF · first branch

00

Applied RF · second branch

00

x/kHz,N/τ  (s−1)x/\mathrm{kHz},\quad N/\tau\;(\mathrm{s^{-1}})

Teal: first branch. Gold: second branch. Points: acquired rates. Fine curves: source expectation. Purple dashes: inference from records. Gray: saved observations. Click the plot to move the probe.

INFER / SOURCE PARAMETERS EXCLUDED

Infer field and spin factor together.

Inferred spin factor

—\text{—}

Inferred shared field

—\text{—}

Spin-factor-two deviance / degree

—\text{—}

First resonance · estimate

—\text{—}

Second resonance · estimate

—\text{—}

Fit deviance / degree

—\text{—}

ri=(Ni−μ^i)/μ^ir_i=(N_i-\widehat\mu_i)/\sqrt{\widehat\mu_i}

Each center and its source rate are profiled from the joint signal/reference likelihood. Both centers are searched over the full displayed interval. At least sixteen distinct coordinates are required. Deviance per degree is descriptive; no confidence interval or discovery significance is reported.

COMPARE / RESTORE

Latest six raw observations
#Offset / kHzFirst / refSecond / ref

CSV includes raw observations, seed, units and source/instrument settings. Source settings are simulator metadata, excluded from inverse estimation. One saved run lasts for this page session.

MODEL / EVIDENCE

What this measurement leaves out.

PJ=0.41+4(ν−νJ)2/w2NJ∼Poisson⁡[τ(SJPJ+b)]\begin{aligned}P_J&=\frac{0.4}{1+4(\nu-\nu_J)^2/w^2}\\N_J&\sim\operatorname{Poisson}[\tau(S_JP_J+b)]\end{aligned}

Known transfer contrast 0.4, width and background 8 per second; independently unknown source rates. Linear LS coupling with no nuclear spin, hyperfine mixing, isotope shifts, state lifetime or atomic-structure corrections. The two electronic manifolds and selectors are idealized; this is not calibrated gallium. A small input spin anomaly is supplied, not calculated from QED. The fixed coarse field only labels RF coordinates.

Steck · LS / Zeeman conventions · Kusch–Foley 1948 · author abstract · historical method only; no original data refit.

Physics tutorial

Atomic Magnetic-Moment Comparator

BackgroundCompare two ideal orbital–spin manifolds in the same magnetic field. Record state-selected atom counts, locate both resonances and separate the electron spin factor from a shared field drift.

Why it mattersA constant is inferred through a calibrated response and retained observations.

Start with the essentials

Focus question
Two resonances. One unknown field.
One-sentence intuition
Keep source assumptions separate from estimates made from records.

Core mathematical model

Two magnetic factors

g1/2=4−gS3g3/2=2+gS3νJ=gJμBBh\begin{aligned}g_{1/2}&=\frac{4-g_S}{3}\\g_{3/2}&=\frac{2+g_S}{3}\\\nu_J&=g_J\frac{\mu_B B}{h}\end{aligned}

Positive factor magnitudes, orbital factor one. Electron magnetic moment opposes angular momentum. Nuclear spin is omitted.

A calibrated frequency coordinate

νJ=gJ(0)(νc+x)νc=μBh(0.5 mT)gJ(0)∈{2/3,4/3}\begin{aligned}\nu_J&=g_J^{(0)}(\nu_c+x)\\\nu_c&=\frac{\mu_B}{h}(0.5\,\mathrm{mT})\\g_J^{(0)}&\in\{2/3,4/3\}\end{aligned}

The scan coordinate is a known frequency mapping; it does not use the unknown true source field or spin factor. Each branch has its own physical RF frequency.

Eliminate the shared field

r=ν^3/2/ν^1/2g^S=4r−21+rB^=h(ν^1/2+ν^3/2)2μB\begin{aligned}r&=\widehat\nu_{3/2}/\widehat\nu_{1/2}\\\widehat g_S&=\frac{4r-2}{1+r}\\\widehat B&=\frac{h(\widehat\nu_{1/2}+\widehat\nu_{3/2})}{2\mu_B}\end{aligned}

Fit both resonance centers and independent source rates from four Poisson exposures per coordinate; then invert their frequencies.

Common difficulties

A simulation supplies its law

Typical misconceptionRecovering a source parameter independently confirms the law.

Better mental modelThese synthetic records test a measurement and inference workflow. They are not historical observations, a parameter confidence interval, or external scientific certification.

Run the experiment

  1. 01

    Find the two centers

    Scan both state selections through the same coarse frequency interval.

    What to observe: The two scaled peaks respond differently to the spin factor.
  2. 02

    Move the field

    Save the run and select the shared-field drift preset.

    What to observe: Both centers move, while the inferred spin factor stays consistent within sampling variation.
  3. 03

    Compare a constrained model

    Choose spin factor two and acquire a fresh scan.

    What to observe: The alternative fits only the shared field and two rates. Deviance is descriptive, not a discovery significance.
FeedbackSomething broken, confusing, or missing on this page?Tell us
What kind of feedback?

Sent with this page’s address, its Lab ID, the site language and your device type. Please leave out personal details. Feedback is kept for up to 12 months.Privacy policy